Attribute.GetCustomAttributes 方法

定义

检索应用于程序集、模块、类型成员或方法参数的自定义属性的数组。Retrieves an array of the custom attributes applied to an assembly, module, type member, or method parameter.

重载

GetCustomAttributes(Module, Type)

检索应用于模块的自定义属性的数组。Retrieves an array of the custom attributes applied to a module. 参数指定模块和要搜索的自定义属性的类型。Parameters specify the module, and the type of the custom attribute to search for.

GetCustomAttributes(ParameterInfo, Type, Boolean)

检索应用于方法参数的自定义属性的数组。Retrieves an array of the custom attributes applied to a method parameter. 参数指定方法参数、要搜索的自定义属性的类型以及是否搜索方法参数的祖先。Parameters specify the method parameter, the type of the custom attribute to search for, and whether to search ancestors of the method parameter.

GetCustomAttributes(Module, Type, Boolean)

检索应用于模块的自定义属性的数组。Retrieves an array of the custom attributes applied to a module. 参数指定模块、要搜索的自定义属性的类型以及忽略的搜索选项。Parameters specify the module, the type of the custom attribute to search for, and an ignored search option.

GetCustomAttributes(MemberInfo, Type, Boolean)

检索应用于类型的成员的自定义属性的数组。Retrieves an array of the custom attributes applied to a member of a type. 参数指定成员、要搜索的自定义属性的类型以及是否搜索成员的祖先。Parameters specify the member, the type of the custom attribute to search for, and whether to search ancestors of the member.

GetCustomAttributes(Assembly, Type, Boolean)

检索一个数组,它由应用于程序集的自定义属性组成。Retrieves an array of the custom attributes applied to an assembly. 参数指定程序集、要搜索的自定义属性的类型以及忽略的搜索选项。Parameters specify the assembly, the type of the custom attribute to search for, and an ignored search option.

GetCustomAttributes(ParameterInfo, Type)

检索应用于方法参数的自定义属性的数组。Retrieves an array of the custom attributes applied to a method parameter. 参数指定方法参数和要搜索的自定义属性的类型。Parameters specify the method parameter, and the type of the custom attribute to search for.

GetCustomAttributes(Module, Boolean)

检索应用于模块的自定义属性的数组。Retrieves an array of the custom attributes applied to a module. 参数指定模块及忽略的搜索选项。Parameters specify the module, and an ignored search option.

GetCustomAttributes(ParameterInfo, Boolean)

检索应用于方法参数的自定义属性的数组。Retrieves an array of the custom attributes applied to a method parameter. 参数指定方法参数以及是否搜索方法参数的祖先。Parameters specify the method parameter, and whether to search ancestors of the method parameter.

GetCustomAttributes(MemberInfo, Boolean)

检索应用于类型的成员的自定义属性的数组。Retrieves an array of the custom attributes applied to a member of a type. 参数指定成员、要搜索的自定义属性的类型以及是否搜索成员的祖先。Parameters specify the member, the type of the custom attribute to search for, and whether to search ancestors of the member.

GetCustomAttributes(Assembly, Type)

检索一个数组,它由应用于程序集的自定义属性组成。Retrieves an array of the custom attributes applied to an assembly. 参数指定程序集和要搜索的自定义属性的类型。Parameters specify the assembly, and the type of the custom attribute to search for.

GetCustomAttributes(Assembly, Boolean)

检索一个数组,它由应用于程序集的自定义属性组成。Retrieves an array of the custom attributes applied to an assembly. 参数指定程序集及忽略的搜索选项。Parameters specify the assembly, and an ignored search option.

GetCustomAttributes(ParameterInfo)

检索应用于方法参数的自定义属性的数组。Retrieves an array of the custom attributes applied to a method parameter. 参数指定方法参数。A parameter specifies the method parameter.

GetCustomAttributes(Module)

检索应用于模块的自定义属性的数组。Retrieves an array of the custom attributes applied to a module. 参数指定模块。A parameter specifies the module.

GetCustomAttributes(MemberInfo)

检索应用于类型的成员的自定义属性的数组。Retrieves an array of the custom attributes applied to a member of a type. 参数指定成员。A parameter specifies the member.

GetCustomAttributes(Assembly)

检索一个数组,它由应用于程序集的自定义属性组成。Retrieves an array of the custom attributes applied to an assembly. 参数指定程序集。A parameter specifies the assembly.

GetCustomAttributes(MemberInfo, Type)

检索应用于类型的成员的自定义属性的数组。Retrieves an array of the custom attributes applied to a member of a type. 参数指定成员和要搜索的自定义属性的类型。Parameters specify the member, and the type of the custom attribute to search for.

GetCustomAttributes(Module, Type)

检索应用于模块的自定义属性的数组。Retrieves an array of the custom attributes applied to a module. 参数指定模块和要搜索的自定义属性的类型。Parameters specify the module, and the type of the custom attribute to search for.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::Module ^ element, Type ^ attributeType);
public static Attribute[] GetCustomAttributes (System.Reflection.Module element, Type attributeType);
static member GetCustomAttributes : System.Reflection.Module * Type -> Attribute[]
Public Shared Function GetCustomAttributes (element As Module, attributeType As Type) As Attribute()

参数

element
Module

一个从 Module 类派生的对象,该类描述可移植的可执行文件。An object derived from the Module class that describes a portable executable file.

attributeType
Type

要搜索的自定义属性的类型或基类型。The type, or a base type, of the custom attribute to search for.

返回

一个 Attribute 数组,包含应用于 attributeTypeelement 类型的自定义属性;如果不存在此类自定义属性,则为空数组。An Attribute array that contains the custom attributes of type attributeType applied to element, or an empty array if no such custom attributes exist.

异常

elementattributeTypenullelement or attributeType is null.

attributeType 不是从 Attribute 派生的。attributeType is not derived from Attribute.

示例

下面的代码示例演示如何使用 GetCustomAttributes,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttributes, taking a Module as a parameter.

using namespace System;
using namespace System::Reflection;
using namespace System::ComponentModel;

// Assign some attributes to the module.
// Set the module's CLSCompliant attribute to false
// The CLSCompliant attribute is applicable for /target:module.
[module:Description("A sample description")];
[module:CLSCompliant(false)];
namespace CustAttrs2CS
{
   ref class DemoClass
   {
   public:
      static void Main()
      {
         Type^ clsType = DemoClass::typeid;

         // Get the Module type to access its metadata.
         Module^ module = clsType->Module;

         // Iterate through all the attributes for the module.
         System::Collections::IEnumerator^ myEnum1 = Attribute::GetCustomAttributes( module )->GetEnumerator();
         while ( myEnum1->MoveNext() )
         {
            Attribute^ attr = safe_cast<Attribute^>(myEnum1->Current);

            // Check for the Description attribute.
            if ( attr->GetType() == DescriptionAttribute::typeid )
                        Console::WriteLine( "Module {0} has the description \"{1}\".", module->Name, (dynamic_cast<DescriptionAttribute^>(attr))->Description );
            // Check for the CLSCompliant attribute.
            else

            // Check for the CLSCompliant attribute.
            if ( attr->GetType() == CLSCompliantAttribute::typeid )
                        Console::WriteLine( "Module {0} {1} CLSCompliant.", module->Name, (dynamic_cast<CLSCompliantAttribute^>(attr))->IsCompliant ? (String^)"is" : "is not" );
         }
      }
   };
}


/*
 * Output:
 * Module CustAttrs2CS.exe is not CLSCompliant.
 * Module CustAttrs2CS.exe has the description "A sample description".
 */
using System;
using System.Reflection;
using System.ComponentModel;

// Assign some attributes to the module.
[module:Description("A sample description")]

// Set the module's CLSCompliant attribute to false
// The CLSCompliant attribute is applicable for /target:module.
[module:CLSCompliant(false)]

namespace CustAttrs2CS {
    class DemoClass {
        static void Main(string[] args) {
            Type clsType = typeof(DemoClass);
            // Get the Module type to access its metadata.
            Module module = clsType.Module;

            // Iterate through all the attributes for the module.
            foreach(Attribute attr in Attribute.GetCustomAttributes(module)) {
                // Check for the Description attribute.
                if (attr.GetType() == typeof(DescriptionAttribute))
                    Console.WriteLine("Module {0} has the description " +
                        "\"{1}\".", module.Name, 
                        ((DescriptionAttribute)attr).Description);
                // Check for the CLSCompliant attribute.
                else if (attr.GetType() == typeof(CLSCompliantAttribute))
                    Console.WriteLine("Module {0} {1} CLSCompliant.",
                        module.Name,
                        ((CLSCompliantAttribute)attr).IsCompliant ? 
                            "is" : "is not");
            }
        }
    }
}

/*
 * Output:
 * Module CustAttrs2CS.exe is not CLSCompliant.
 * Module CustAttrs2CS.exe has the description "A sample description".
 */
Imports System.Reflection
Imports System.ComponentModel

' Give the Module some attributes.
<Module: Description("A sample description")> 

' Make the CLSCompliant attribute False.
' The CLSCompliant attribute is applicable for /target:module.
<Module: CLSCompliant(False)> 

Module DemoModule

    Sub Main()
        ' Get the Module type to access its metadata.
        Dim modType As Reflection.Module = GetType(DemoModule).Module
        Dim attr As Attribute
        ' Iterate through all the attributes for the module.
        For Each attr In Attribute.GetCustomAttributes(modType)
            ' Check for the Description attribute.
            If TypeOf attr Is DescriptionAttribute Then
                ' Convert the attribute to access its data.
                Dim descAttr As DescriptionAttribute = _
                    CType(attr, DescriptionAttribute)
                Console.WriteLine("Module {0} has the description ""{1}"".", _
                    modType.Name, descAttr.Description)

            ' Check for the CLSCompliant attribute.
            ElseIf TypeOf attr Is CLSCompliantAttribute Then
                ' Convert the attribute to access its data.
                Dim CLSCompAttr As CLSCompliantAttribute = _
                    CType(attr, CLSCompliantAttribute)
                Dim strCompliant As String
                If CLSCompAttr.IsCompliant Then
                    strCompliant = "is"
                Else
                    strCompliant = "is not"
                End If
                Console.WriteLine("Module {0} {1} CLSCompliant.", _
                    modType.Name, strCompliant)
            End If
        Next
    End Sub
End Module

' Output:
' Module CustAttrs2VB.exe has the description "A sample description".
' Module CustAttrs2VB.exe is not CLSCompliant.

GetCustomAttributes(ParameterInfo, Type, Boolean)

检索应用于方法参数的自定义属性的数组。Retrieves an array of the custom attributes applied to a method parameter. 参数指定方法参数、要搜索的自定义属性的类型以及是否搜索方法参数的祖先。Parameters specify the method parameter, the type of the custom attribute to search for, and whether to search ancestors of the method parameter.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::ParameterInfo ^ element, Type ^ attributeType, bool inherit);
public static Attribute[] GetCustomAttributes (System.Reflection.ParameterInfo element, Type attributeType, bool inherit);
static member GetCustomAttributes : System.Reflection.ParameterInfo * Type * bool -> Attribute[]
Public Shared Function GetCustomAttributes (element As ParameterInfo, attributeType As Type, inherit As Boolean) As Attribute()

参数

element
ParameterInfo

一个从 ParameterInfo 类派生的对象,该类描述类成员的参数。An object derived from the ParameterInfo class that describes a parameter of a member of a class.

attributeType
Type

要搜索的自定义属性的类型或基类型。The type, or a base type, of the custom attribute to search for.

inherit
Boolean

如果为 true,则指定还在 element 的祖先中搜索自定义属性。If true, specifies to also search the ancestors of element for custom attributes.

返回

一个 Attribute 数组,包含应用于 attributeTypeelement 类型的自定义属性;如果不存在此类自定义属性,则为空数组。An Attribute array that contains the custom attributes of type attributeType applied to element, or an empty array if no such custom attributes exist.

异常

elementattributeTypenullelement or attributeType is null.

attributeType 不是从 Attribute 派生的。attributeType is not derived from Attribute.

无法加载自定义属性类型。A custom attribute type cannot be loaded.

示例

下面的代码示例演示如何使用 GetCustomAttributes,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttributes, taking a ParameterInfo as a parameter.

using namespace System;
using namespace System::Reflection;
using namespace System::ComponentModel;

namespace CustAttrs5CS
{
   public ref class AClass
   {
   public:
      void ParamArrayAndDesc(
         // Add ParamArray and Description attributes.
         [Description("This argument is a ParamArray")]
         array<Int32>^args )
      {}
   };

   ref class DemoClass
   {
   public:
      static void Main()
      {
         // Get the Class type to access its metadata.
         Type^ clsType = AClass::typeid;

         // Get the type information for the method.
         MethodInfo^ mInfo = clsType->GetMethod( "ParamArrayAndDesc" );
         if ( mInfo != nullptr )
         {
            // Get the parameter information.
            array<ParameterInfo^>^pInfo = mInfo->GetParameters();
            if ( pInfo != nullptr )
            {
               // Iterate through all the attributes for the parameter.
               System::Collections::IEnumerator^ myEnum4 = Attribute::GetCustomAttributes( pInfo[ 0 ] )->GetEnumerator();
               while ( myEnum4->MoveNext() )
               {
                  Attribute^ attr = safe_cast<Attribute^>(myEnum4->Current);

                  // Check for the ParamArray attribute.
                  if ( attr->GetType() == ParamArrayAttribute::typeid )
                                    Console::WriteLine( "Parameter {0} for method {1} "
                  "has the ParamArray attribute.", pInfo[ 0 ]->Name, mInfo->Name );
                  // Check for the Description attribute.
                  else

                  // Check for the Description attribute.
                  if ( attr->GetType() == DescriptionAttribute::typeid )
                  {
                     Console::WriteLine( "Parameter {0} for method {1} "
                     "has a description attribute.", pInfo[ 0 ]->Name, mInfo->Name );
                     Console::WriteLine( "The description is: \"{0}\"", (dynamic_cast<DescriptionAttribute^>(attr))->Description );
                  }
               }
            }
         }
      }
   };
}

/*
 * Output:
 * Parameter args for method ParamArrayAndDesc has a description attribute.
 * The description is: "This argument is a ParamArray"
 * Parameter args for method ParamArrayAndDesc has the ParamArray attribute.
 */
using System;
using System.Reflection;
using System.ComponentModel;

namespace CustAttrs5CS {
    public class AClass {
        public void ParamArrayAndDesc(
            // Add ParamArray (with the keyword) and Description attributes.
            [Description("This argument is a ParamArray")]
            params int[] args)
        {}
    }

    class DemoClass {
        static void Main(string[] args) {
            // Get the Class type to access its metadata.
            Type clsType = typeof(AClass);
            // Get the type information for the method.
            MethodInfo mInfo = clsType.GetMethod("ParamArrayAndDesc");
            if (mInfo != null) {
                // Get the parameter information.
                ParameterInfo[] pInfo = mInfo.GetParameters();
                if (pInfo != null) {
                    // Iterate through all the attributes for the parameter.
                    foreach(Attribute attr in 
                        Attribute.GetCustomAttributes(pInfo[0])) {
                        // Check for the ParamArray attribute.
                        if (attr.GetType() == typeof(ParamArrayAttribute))
                            Console.WriteLine("Parameter {0} for method {1} " +
                                "has the ParamArray attribute.",
                                pInfo[0].Name, mInfo.Name);
                        // Check for the Description attribute.
                        else if (attr.GetType() == 
                            typeof(DescriptionAttribute)) {
                            Console.WriteLine("Parameter {0} for method {1} " +
                                "has a description attribute.",
                                pInfo[0].Name, mInfo.Name);
                            Console.WriteLine("The description is: \"{0}\"",
                                ((DescriptionAttribute)attr).Description);
                        }
                    }
                }
            }
        }
    }
}

/*
 * Output:
 * Parameter args for method ParamArrayAndDesc has a description attribute.
 * The description is: "This argument is a ParamArray"
 * Parameter args for method ParamArrayAndDesc has the ParamArray attribute.
 */
Imports System.Reflection
Imports System.ComponentModel

Module DemoModule
    Public Class AClass
        ' Add Description and ParamArray (with the keyword) attributes.
        Public Sub ParamArrayAndDesc( _
            <Description("This argument is a ParamArray")> _
            ByVal ParamArray args() As Integer)
        End Sub
    End Class

    Sub Main()
        ' Get the Class type to access its metadata.
        Dim clsType As Type = GetType(AClass)
        ' Get the type information for the method.
        Dim mInfo As MethodInfo = clsType.GetMethod("ParamArrayAndDesc")
        ' Get the Parameter information for the method.
        Dim pInfo() As ParameterInfo = mInfo.GetParameters()
        Dim attr As Attribute
        ' Iterate through each attribute of the parameter.
        For Each attr In Attribute.GetCustomAttributes(pInfo(0))
            ' Check for the ParamArray attribute.
            If TypeOf attr Is ParamArrayAttribute Then
                ' Convert the attribute to access its data.
                Dim paAttr As ParamArrayAttribute = _
                    CType(attr, ParamArrayAttribute)
                Console.WriteLine("Parameter {0} has the " + _
                    "ParamArray attribute.", pInfo(0).Name)
            ' Check for the Description attribute.
            ElseIf TypeOf attr Is DescriptionAttribute Then
                ' Convert the attribute to access its data.
                Dim descAttr As DescriptionAttribute = _
                    CType(attr, DescriptionAttribute)
                Console.WriteLine("Parameter {0} has a description " + _
                    "attribute. The description is:", pInfo(0).Name)
                Console.WriteLine(descAttr.Description)
            End If
        Next
    End Sub
End Module

' Output:
' Parameter args has a description attribute. The description is:
' This argument is a ParamArray
' Parameter args has the ParamArray attribute.

注解

如果 element 表示派生类型的方法中的参数,则返回值包括应用于重写的基方法中的相同参数的可继承自定义特性。If element represents a parameter in a method of a derived type, the return value includes the inheritable custom attributes applied to the same parameter in the overridden base methods.

GetCustomAttributes(Module, Type, Boolean)

检索应用于模块的自定义属性的数组。Retrieves an array of the custom attributes applied to a module. 参数指定模块、要搜索的自定义属性的类型以及忽略的搜索选项。Parameters specify the module, the type of the custom attribute to search for, and an ignored search option.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::Module ^ element, Type ^ attributeType, bool inherit);
public static Attribute[] GetCustomAttributes (System.Reflection.Module element, Type attributeType, bool inherit);
static member GetCustomAttributes : System.Reflection.Module * Type * bool -> Attribute[]
Public Shared Function GetCustomAttributes (element As Module, attributeType As Type, inherit As Boolean) As Attribute()

参数

element
Module

一个从 Module 类派生的对象,该类描述可移植的可执行文件。An object derived from the Module class that describes a portable executable file.

attributeType
Type

要搜索的自定义属性的类型或基类型。The type, or a base type, of the custom attribute to search for.

inherit
Boolean

此参数被忽略,并且不会影响此方法的操作。This parameter is ignored, and does not affect the operation of this method.

返回

一个 Attribute 数组,包含应用于 attributeTypeelement 类型的自定义属性;如果不存在此类自定义属性,则为空数组。An Attribute array that contains the custom attributes of type attributeType applied to element, or an empty array if no such custom attributes exist.

异常

elementattributeTypenullelement or attributeType is null.

attributeType 不是从 Attribute 派生的。attributeType is not derived from Attribute.

示例

下面的代码示例演示如何使用 GetCustomAttributes,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttributes, taking a Module as a parameter.

using namespace System;
using namespace System::Reflection;
using namespace System::ComponentModel;

// Assign some attributes to the module.
// Set the module's CLSCompliant attribute to false
// The CLSCompliant attribute is applicable for /target:module.
[module:Description("A sample description")];
[module:CLSCompliant(false)];
namespace CustAttrs2CS
{
   ref class DemoClass
   {
   public:
      static void Main()
      {
         Type^ clsType = DemoClass::typeid;

         // Get the Module type to access its metadata.
         Module^ module = clsType->Module;

         // Iterate through all the attributes for the module.
         System::Collections::IEnumerator^ myEnum1 = Attribute::GetCustomAttributes( module )->GetEnumerator();
         while ( myEnum1->MoveNext() )
         {
            Attribute^ attr = safe_cast<Attribute^>(myEnum1->Current);

            // Check for the Description attribute.
            if ( attr->GetType() == DescriptionAttribute::typeid )
                        Console::WriteLine( "Module {0} has the description \"{1}\".", module->Name, (dynamic_cast<DescriptionAttribute^>(attr))->Description );
            // Check for the CLSCompliant attribute.
            else

            // Check for the CLSCompliant attribute.
            if ( attr->GetType() == CLSCompliantAttribute::typeid )
                        Console::WriteLine( "Module {0} {1} CLSCompliant.", module->Name, (dynamic_cast<CLSCompliantAttribute^>(attr))->IsCompliant ? (String^)"is" : "is not" );
         }
      }
   };
}


/*
 * Output:
 * Module CustAttrs2CS.exe is not CLSCompliant.
 * Module CustAttrs2CS.exe has the description "A sample description".
 */
using System;
using System.Reflection;
using System.ComponentModel;

// Assign some attributes to the module.
[module:Description("A sample description")]

// Set the module's CLSCompliant attribute to false
// The CLSCompliant attribute is applicable for /target:module.
[module:CLSCompliant(false)]

namespace CustAttrs2CS {
    class DemoClass {
        static void Main(string[] args) {
            Type clsType = typeof(DemoClass);
            // Get the Module type to access its metadata.
            Module module = clsType.Module;

            // Iterate through all the attributes for the module.
            foreach(Attribute attr in Attribute.GetCustomAttributes(module)) {
                // Check for the Description attribute.
                if (attr.GetType() == typeof(DescriptionAttribute))
                    Console.WriteLine("Module {0} has the description " +
                        "\"{1}\".", module.Name, 
                        ((DescriptionAttribute)attr).Description);
                // Check for the CLSCompliant attribute.
                else if (attr.GetType() == typeof(CLSCompliantAttribute))
                    Console.WriteLine("Module {0} {1} CLSCompliant.",
                        module.Name,
                        ((CLSCompliantAttribute)attr).IsCompliant ? 
                            "is" : "is not");
            }
        }
    }
}

/*
 * Output:
 * Module CustAttrs2CS.exe is not CLSCompliant.
 * Module CustAttrs2CS.exe has the description "A sample description".
 */
Imports System.Reflection
Imports System.ComponentModel

' Give the Module some attributes.
<Module: Description("A sample description")> 

' Make the CLSCompliant attribute False.
' The CLSCompliant attribute is applicable for /target:module.
<Module: CLSCompliant(False)> 

Module DemoModule

    Sub Main()
        ' Get the Module type to access its metadata.
        Dim modType As Reflection.Module = GetType(DemoModule).Module
        Dim attr As Attribute
        ' Iterate through all the attributes for the module.
        For Each attr In Attribute.GetCustomAttributes(modType)
            ' Check for the Description attribute.
            If TypeOf attr Is DescriptionAttribute Then
                ' Convert the attribute to access its data.
                Dim descAttr As DescriptionAttribute = _
                    CType(attr, DescriptionAttribute)
                Console.WriteLine("Module {0} has the description ""{1}"".", _
                    modType.Name, descAttr.Description)

            ' Check for the CLSCompliant attribute.
            ElseIf TypeOf attr Is CLSCompliantAttribute Then
                ' Convert the attribute to access its data.
                Dim CLSCompAttr As CLSCompliantAttribute = _
                    CType(attr, CLSCompliantAttribute)
                Dim strCompliant As String
                If CLSCompAttr.IsCompliant Then
                    strCompliant = "is"
                Else
                    strCompliant = "is not"
                End If
                Console.WriteLine("Module {0} {1} CLSCompliant.", _
                    modType.Name, strCompliant)
            End If
        Next
    End Sub
End Module

' Output:
' Module CustAttrs2VB.exe has the description "A sample description".
' Module CustAttrs2VB.exe is not CLSCompliant.

注解

如果 inherit @no__t 为-2,则返回值将包含 element 的祖先的自定义属性。The return value contains the custom attributes for ancestors of element if inherit is true.

GetCustomAttributes(MemberInfo, Type, Boolean)

检索应用于类型的成员的自定义属性的数组。Retrieves an array of the custom attributes applied to a member of a type. 参数指定成员、要搜索的自定义属性的类型以及是否搜索成员的祖先。Parameters specify the member, the type of the custom attribute to search for, and whether to search ancestors of the member.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::MemberInfo ^ element, Type ^ type, bool inherit);
public static Attribute[] GetCustomAttributes (System.Reflection.MemberInfo element, Type type, bool inherit);
static member GetCustomAttributes : System.Reflection.MemberInfo * Type * bool -> Attribute[]

参数

element
MemberInfo

一个从 MemberInfo 类派生的对象,该类描述类的构造函数、事件、字段、方法或属性成员。An object derived from the MemberInfo class that describes a constructor, event, field, method, or property member of a class.

type
Type

要搜索的自定义属性的类型或基类型。The type, or a base type, of the custom attribute to search for.

inherit
Boolean

如果为 true,则指定还在 element 的祖先中搜索自定义属性。If true, specifies to also search the ancestors of element for custom attributes.

返回

一个 Attribute 数组,包含应用于 typeelement 类型的自定义属性;如果不存在此类自定义属性,则为空数组。An Attribute array that contains the custom attributes of type type applied to element, or an empty array if no such custom attributes exist.

异常

elementtypenullelement or type is null.

type 不是从 Attribute 派生的。type is not derived from Attribute.

element 不是构造函数、方法、属性、事件、类型或字段。element is not a constructor, method, property, event, type, or field.

无法加载自定义属性类型。A custom attribute type cannot be loaded.

示例

下面的代码示例演示如何使用 GetCustomAttributes,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttributes, taking a MemberInfo as a parameter.

using namespace System;
using namespace System::Reflection;
using namespace System::Security;
using namespace System::Runtime::InteropServices;

namespace CustAttrs4CS
{
   // Create a class for Win32 imported unmanaged functions.
   public ref class Win32
   {
   public:

      [DllImport("user32.dll", CharSet = CharSet::Unicode)]
      static int MessageBox( int hWnd, String^ text, String^ caption, UInt32 type );
   };

   public ref class AClass
   {
   public:

      // Add some attributes to the Win32CallMethod.

      [Obsolete("This method is obsolete. Use managed MsgBox instead.")]
      void Win32CallMethod()
      {
         Win32::MessageBox( 0, "This is an unmanaged call.", "Be Careful!", 0 );
      }

   };

   ref class DemoClass
   {
   public:
      static void Main()
      {
         // Get the Class type to access its metadata.
         Type^ clsType = AClass::typeid;

         // Get the type information for the Win32CallMethod.
         MethodInfo^ mInfo = clsType->GetMethod( "Win32CallMethod" );
         if ( mInfo != nullptr )
         {
            // Iterate through all the attributes for the method.
            System::Collections::IEnumerator^ myEnum3 = Attribute::GetCustomAttributes( mInfo )->GetEnumerator();
            while ( myEnum3->MoveNext() )
            {
               Attribute^ attr = safe_cast<Attribute^>(myEnum3->Current);

               // Check for the Obsolete attribute.
               if ( attr->GetType() == ObsoleteAttribute::typeid )
               {
                  Console::WriteLine( "Method {0} is obsolete. "
                  "The message is:", mInfo->Name );
                  Console::WriteLine( (dynamic_cast<ObsoleteAttribute^>(attr))->Message );
               }
               // Check for the SuppressUnmanagedCodeSecurity attribute.
               else

               // Check for the SuppressUnmanagedCodeSecurity attribute.
               if ( attr->GetType() == SuppressUnmanagedCodeSecurityAttribute::typeid )
               {
                  Console::WriteLine( "This method calls unmanaged code "
                  "with no security check." );
                  Console::WriteLine( "Please do not use unless absolutely necessary." );
                  AClass^ myCls = gcnew AClass;
                  myCls->Win32CallMethod();
               }
            }
         }
      }
   };
}


/*
 * Output:
 * Method Win32CallMethod is obsolete. The message is:
 * This method is obsolete. Use managed MsgBox instead.
 * This method calls unmanaged code with no security check.
 * Please do not use unless absolutely necessary.
 */
using System;
using System.Reflection;
using System.Security;
using System.Runtime.InteropServices;

namespace CustAttrs4CS
{

    // Define an enumeration of Win32 unmanaged types
    public enum UnmanagedType
    {
        User,
        GDI,
        Kernel,
        Shell,
        Networking,
        Multimedia
    }

    // Define the Unmanaged attribute.
    public class UnmanagedAttribute : Attribute
    {
        // Storage for the UnmanagedType value.
        protected UnmanagedType thisType;

        // Set the unmanaged type in the constructor.
        public UnmanagedAttribute(UnmanagedType type)
        {
            thisType = type;
        }

        // Define a property to get and set the UnmanagedType value.
        public UnmanagedType Win32Type
        {
            get { return thisType; }
            set { thisType = Win32Type; }
        }
    }

    // Create a class for an imported Win32 unmanaged function.
    public class Win32 {
        [DllImport("user32.dll", CharSet = CharSet.Unicode)]
        public static extern int MessageBox(int hWnd, String text,
            String caption, uint type);
    }

    public class AClass {
        // Add some attributes to Win32CallMethod.
        [Obsolete("This method is obsolete. Use managed MsgBox instead.")]
        [Unmanaged(UnmanagedType.User)]
        public void Win32CallMethod()
        {
            Win32.MessageBox(0, "This is an unmanaged call.", "Caution!", 0);
        }
    }

    class DemoClass {
        static void Main(string[] args)
            {
            // Get the AClass type to access its metadata.
            Type clsType = typeof(AClass);
            // Get the type information for Win32CallMethod.
            MethodInfo mInfo = clsType.GetMethod("Win32CallMethod");
            if (mInfo != null)
            {
                // Iterate through all the attributes of the method.
                foreach(Attribute attr in
                    Attribute.GetCustomAttributes(mInfo)) {
                    // Check for the Obsolete attribute.
                    if (attr.GetType() == typeof(ObsoleteAttribute))
                    {
                        Console.WriteLine("Method {0} is obsolete. " +
                            "The message is:",
                            mInfo.Name);
                        Console.WriteLine("  \"{0}\"",
                            ((ObsoleteAttribute)attr).Message);
                    }

                    // Check for the Unmanaged attribute.
                    else if (attr.GetType() == typeof(UnmanagedAttribute))
                    {
                        Console.WriteLine(
                            "This method calls unmanaged code.");
                        Console.WriteLine(
                            String.Format("The Unmanaged attribute type is {0}.",
                                          ((UnmanagedAttribute)attr).Win32Type));
                        AClass myCls = new AClass();
                        myCls.Win32CallMethod();
                    }
                }
            }
        }
    }
}

/*

This code example produces the following results.

First, the compilation yields the warning, "...This method is
obsolete. Use managed MsgBox instead."
Second, execution yields a message box with a title of "Caution!"
and message text of "This is an unmanaged call."
Third, the following text is displayed in the console window:

Method Win32CallMethod is obsolete. The message is:
  "This method is obsolete. Use managed MsgBox instead."
This method calls unmanaged code.
The Unmanaged attribute type is User.

*/

Imports System.Reflection
Imports System.Security
Imports System.Runtime.InteropServices

' Define an enumeration of Win32 unmanaged types
Public Enum UnmanagedType
    User
    GDI
    Kernel
    Shell
    Networking
    Multimedia
End Enum 'UnmanagedType

' Define the Unmanaged attribute.
Public Class UnmanagedAttribute 
             Inherits Attribute

    ' Storage for the UnmanagedType value.
    Protected thisType As UnmanagedType
    
    ' Set the unmanaged type in the constructor.
    Public Sub New(ByVal type As UnmanagedType) 
        thisType = type
    End Sub
    
    ' Define a property to get and set the UnmanagedType value.
    Public Property Win32Type() As UnmanagedType 
        Get
            Return thisType
        End Get
        Set
            thisType = Win32Type
        End Set
    End Property
End Class

' Create a class for an imported Win32 unmanaged function.
Public Class Win32
    <DllImport("user32.dll", CharSet:=CharSet.Unicode)> _
    Public Shared Function MessageBox(ByVal hWnd As Integer, _
                                      ByVal Text As String, _
                                      ByVal caption As String, _
                                      ByVal type As Integer) As Integer
    End Function 'MessageBox
End Class

Public Class AClass
    ' Add some attributes to Win32CallMethod.
    <Obsolete("This method is obsolete. Use managed MsgBox instead."), _
     Unmanaged(UnmanagedType.User)>  _
    Public Sub Win32CallMethod() 
        Win32.MessageBox(0, "This is an unmanaged call.", "Caution!", 0)    
    End Sub
End Class

Class DemoClass
    Shared Sub Main(ByVal args() As String) 
        ' Get the AClass type to access its metadata.
        Dim clsType As Type = GetType(AClass)
        ' Get the type information for Win32CallMethod.
        Dim mInfo As MethodInfo = clsType.GetMethod("Win32CallMethod")
        If Not (mInfo Is Nothing) Then
            ' Iterate through all the attributes of the method.
            Dim attr As Attribute
            For Each attr In  Attribute.GetCustomAttributes(mInfo)
                ' Check for the Obsolete attribute.
                If attr.GetType().Equals(GetType(ObsoleteAttribute)) Then
                    Console.WriteLine("Method {0} is obsolete. The message is:", mInfo.Name)
                    Console.WriteLine("  ""{0}""", CType(attr, ObsoleteAttribute).Message)
                ' Check for the Unmanaged attribute.
                ElseIf attr.GetType().Equals(GetType(UnmanagedAttribute)) Then
                    Console.WriteLine("This method calls unmanaged code.")
                    Console.WriteLine( _
                            String.Format("The Unmanaged attribute type is {0}.", _
                            CType(attr, UnmanagedAttribute).Win32Type))
                    Dim myCls As New AClass()
                    myCls.Win32CallMethod()
                End If
            Next attr
        End If
    End Sub
End Class

'
'This code example produces the following results. 
'
'First, the compilation yields the warning, "...This method is 
'obsolete. Use managed MsgBox instead."
'Second, execution yields a message box with a title of "Caution!" 
'and message text of "This is an unmanaged call." 
'Third, the following text is displayed in the console window:
'
'Method Win32CallMethod is obsolete. The message is:
'  "This method is obsolete. Use managed MsgBox instead."
'This method calls unmanaged code.
'The Unmanaged attribute type is User.
' 

注解

如果 inherit @no__t 为-2,则返回值将包含 element 的祖先的自定义属性。The return value contains the custom attributes for ancestors of element if inherit is true.

备注

从 .NET Framework 版本2.0 开始,如果属性以新的元数据格式存储,则此方法将返回方法、构造函数和类型的安全特性。Starting with the .NET Framework version 2.0, this method returns security attributes on methods, constructors, and types if the attributes are stored in the new metadata format. 使用版本2.0 或更高版本编译的程序集将使用新的格式。Assemblies compiled with version 2.0 or later use the new format. 使用早期版本的 .NET Framework 编译的动态程序集和程序集使用旧的 XML 格式。Dynamic assemblies and assemblies compiled with earlier versions of the .NET Framework use the old XML format. 请参阅发出声明性安全特性See Emitting Declarative Security Attributes.

GetCustomAttributes(Assembly, Type, Boolean)

检索一个数组,它由应用于程序集的自定义属性组成。Retrieves an array of the custom attributes applied to an assembly. 参数指定程序集、要搜索的自定义属性的类型以及忽略的搜索选项。Parameters specify the assembly, the type of the custom attribute to search for, and an ignored search option.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::Assembly ^ element, Type ^ attributeType, bool inherit);
public static Attribute[] GetCustomAttributes (System.Reflection.Assembly element, Type attributeType, bool inherit);
static member GetCustomAttributes : System.Reflection.Assembly * Type * bool -> Attribute[]
Public Shared Function GetCustomAttributes (element As Assembly, attributeType As Type, inherit As Boolean) As Attribute()

参数

element
Assembly

一个派生自 Assembly 类的对象,用于描述模块的可重用集合。An object derived from the Assembly class that describes a reusable collection of modules.

attributeType
Type

要搜索的自定义属性的类型或基类型。The type, or a base type, of the custom attribute to search for.

inherit
Boolean

此参数被忽略,并且不会影响此方法的操作。This parameter is ignored, and does not affect the operation of this method.

返回

一个 Attribute 数组,包含应用于 attributeTypeelement 类型的自定义属性;如果不存在此类自定义属性,则为空数组。An Attribute array that contains the custom attributes of type attributeType applied to element, or an empty array if no such custom attributes exist.

异常

elementattributeTypenullelement or attributeType is null.

attributeType 不是从 Attribute 派生的。attributeType is not derived from Attribute.

示例

下面的代码示例演示如何使用 GetCustomAttributes,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttributes, taking an Assembly as a parameter.

using namespace System;
using namespace System::Reflection;

[assembly:AssemblyTitle("CustAttrs1CPP")];
[assembly:AssemblyDescription("GetCustomAttributes() Demo")];
[assembly:AssemblyCompany("Microsoft")];

ref class Example
{};

static void main()
{
    Type^ clsType = Example::typeid;

    // Get the Assembly type to access its metadata.
    Assembly^ assy = clsType->Assembly;

    // Iterate through the attributes for the assembly.
    System::Collections::IEnumerator^ myEnum = Attribute::GetCustomAttributes( assy )->GetEnumerator();
    while ( myEnum->MoveNext() )
    {
       Attribute^ attr = safe_cast<Attribute^>(myEnum->Current);

       // Check for the AssemblyTitle attribute.
       if ( attr->GetType() == AssemblyTitleAttribute::typeid )
          Console::WriteLine( "Assembly title is \"{0}\".", (dynamic_cast<AssemblyTitleAttribute^>(attr))->Title );
          // Check for the AssemblyDescription attribute.
       else
          // Check for the AssemblyDescription attribute.
          if ( attr->GetType() == AssemblyDescriptionAttribute::typeid )
             Console::WriteLine( "Assembly description is \"{0}\".", (dynamic_cast<AssemblyDescriptionAttribute^>(attr))->Description );
          // Check for the AssemblyCompany attribute.
          else if ( attr->GetType() == AssemblyCompanyAttribute::typeid )
             Console::WriteLine( "Assembly company is {0}.", (dynamic_cast<AssemblyCompanyAttribute^>(attr))->Company );
    }
}
// The example displays the following output:
//     Assembly description is "GetCustomAttributes() Demo".
//     Assembly company is Microsoft.
//     Assembly title is "CustAttrs1CPP".
using System;
using System.Reflection;

[assembly: AssemblyTitle("CustAttrs1CS")]
[assembly: AssemblyDescription("GetCustomAttributes() Demo")]
[assembly: AssemblyCompany("Microsoft")]

class Example {
    static void Main() {
        // Get the Assembly object to access its metadata.
        Assembly assy = typeof(Example).Assembly;

        // Iterate through the attributes for the assembly.
        foreach(Attribute attr in Attribute.GetCustomAttributes(assy)) {
            // Check for the AssemblyTitle attribute.
            if (attr.GetType() == typeof(AssemblyTitleAttribute))
                Console.WriteLine("Assembly title is \"{0}\".",
                    ((AssemblyTitleAttribute)attr).Title);

            // Check for the AssemblyDescription attribute.
            else if (attr.GetType() == 
                typeof(AssemblyDescriptionAttribute))
                Console.WriteLine("Assembly description is \"{0}\".",
                    ((AssemblyDescriptionAttribute)attr).Description);

            // Check for the AssemblyCompany attribute.
            else if (attr.GetType() == typeof(AssemblyCompanyAttribute))
                Console.WriteLine("Assembly company is {0}.",
                    ((AssemblyCompanyAttribute)attr).Company);
        }
   }
}
// The example displays the following output:
//     Assembly title is "CustAttrs1CS".
//     Assembly description is "GetCustomAttributes() Demo".
//     Assembly company is Microsoft.
Imports System.Reflection

<Assembly: AssemblyTitle("CustAttrs1VB")> 
<Assembly: AssemblyDescription("GetCustomAttributes() Demo")> 
<Assembly: AssemblyCompany("Microsoft")> 

Module Example
    Sub Main()
        ' Get the Assembly type to access its metadata.
        Dim assy As Reflection.Assembly = GetType(Example).Assembly

        ' Iterate through all the attributes for the assembly.
        For Each attr As Attribute In Attribute.GetCustomAttributes(assy)
            ' Check for the AssemblyTitle attribute.
            If TypeOf attr Is AssemblyTitleAttribute Then
                ' Convert the attribute to access its data.
                Dim attrTitle As AssemblyTitleAttribute = _
                    CType(attr, AssemblyTitleAttribute)
                Console.WriteLine("Assembly title is ""{0}"".", _
                    attrTitle.Title)

            ' Check for the AssemblyDescription attribute.
            ElseIf TypeOf attr Is AssemblyDescriptionAttribute Then
                ' Convert the attribute to access its data.
                Dim attrDesc As AssemblyDescriptionAttribute = _
                    CType(attr, AssemblyDescriptionAttribute)
                Console.WriteLine("Assembly description is ""{0}"".", _
                    attrDesc.Description)

            ' Check for the AssemblyCompany attribute.
            ElseIf TypeOf attr Is AssemblyCompanyAttribute Then
                ' Convert the attribute to access its data.
                Dim attrComp As AssemblyCompanyAttribute = _
                    CType(attr, AssemblyCompanyAttribute)
                Console.WriteLine("Assembly company is {0}.", _
                    attrComp.Company)
            End If
        Next
    End Sub
End Module
' The example displays the following output:
'     Assembly company is Microsoft.
'     Assembly description is "GetCustomAttributes() Demo".
'     Assembly title is "CustAttrs1VB".

注解

备注

从 .NET Framework 版本2.0 开始,如果属性以新的元数据格式存储,则此方法返回安全特性。Starting with the .NET Framework version 2.0, this method returns security attributes if the attributes are stored in the new metadata format. 使用版本2.0 或更高版本编译的程序集将使用新的格式。Assemblies compiled with version 2.0 or later use the new format. 使用早期版本的 .NET Framework 编译的动态程序集和程序集使用旧的 XML 格式。Dynamic assemblies and assemblies compiled with earlier versions of the .NET Framework use the old XML format. 请参阅发出声明性安全特性See Emitting Declarative Security Attributes.

GetCustomAttributes(ParameterInfo, Type)

检索应用于方法参数的自定义属性的数组。Retrieves an array of the custom attributes applied to a method parameter. 参数指定方法参数和要搜索的自定义属性的类型。Parameters specify the method parameter, and the type of the custom attribute to search for.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::ParameterInfo ^ element, Type ^ attributeType);
public static Attribute[] GetCustomAttributes (System.Reflection.ParameterInfo element, Type attributeType);
static member GetCustomAttributes : System.Reflection.ParameterInfo * Type -> Attribute[]
Public Shared Function GetCustomAttributes (element As ParameterInfo, attributeType As Type) As Attribute()

参数

element
ParameterInfo

一个从 ParameterInfo 类派生的对象,该类描述类成员的参数。An object derived from the ParameterInfo class that describes a parameter of a member of a class.

attributeType
Type

要搜索的自定义属性的类型或基类型。The type, or a base type, of the custom attribute to search for.

返回

一个 Attribute 数组,包含应用于 attributeTypeelement 类型的自定义属性;如果不存在此类自定义属性,则为空数组。An Attribute array that contains the custom attributes of type attributeType applied to element, or an empty array if no such custom attributes exist.

异常

elementattributeTypenullelement or attributeType is null.

attributeType 不是从 Attribute 派生的。attributeType is not derived from Attribute.

无法加载自定义属性类型。A custom attribute type cannot be loaded.

示例

下面的代码示例演示如何使用 GetCustomAttributes,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttributes, taking a ParameterInfo as a parameter.

using namespace System;
using namespace System::Reflection;
using namespace System::ComponentModel;

namespace CustAttrs5CS
{
   public ref class AClass
   {
   public:
      void ParamArrayAndDesc(
         // Add ParamArray and Description attributes.
         [Description("This argument is a ParamArray")]
         array<Int32>^args )
      {}
   };

   ref class DemoClass
   {
   public:
      static void Main()
      {
         // Get the Class type to access its metadata.
         Type^ clsType = AClass::typeid;

         // Get the type information for the method.
         MethodInfo^ mInfo = clsType->GetMethod( "ParamArrayAndDesc" );
         if ( mInfo != nullptr )
         {
            // Get the parameter information.
            array<ParameterInfo^>^pInfo = mInfo->GetParameters();
            if ( pInfo != nullptr )
            {
               // Iterate through all the attributes for the parameter.
               System::Collections::IEnumerator^ myEnum4 = Attribute::GetCustomAttributes( pInfo[ 0 ] )->GetEnumerator();
               while ( myEnum4->MoveNext() )
               {
                  Attribute^ attr = safe_cast<Attribute^>(myEnum4->Current);

                  // Check for the ParamArray attribute.
                  if ( attr->GetType() == ParamArrayAttribute::typeid )
                                    Console::WriteLine( "Parameter {0} for method {1} "
                  "has the ParamArray attribute.", pInfo[ 0 ]->Name, mInfo->Name );
                  // Check for the Description attribute.
                  else

                  // Check for the Description attribute.
                  if ( attr->GetType() == DescriptionAttribute::typeid )
                  {
                     Console::WriteLine( "Parameter {0} for method {1} "
                     "has a description attribute.", pInfo[ 0 ]->Name, mInfo->Name );
                     Console::WriteLine( "The description is: \"{0}\"", (dynamic_cast<DescriptionAttribute^>(attr))->Description );
                  }
               }
            }
         }
      }
   };
}

/*
 * Output:
 * Parameter args for method ParamArrayAndDesc has a description attribute.
 * The description is: "This argument is a ParamArray"
 * Parameter args for method ParamArrayAndDesc has the ParamArray attribute.
 */
using System;
using System.Reflection;
using System.ComponentModel;

namespace CustAttrs5CS {
    public class AClass {
        public void ParamArrayAndDesc(
            // Add ParamArray (with the keyword) and Description attributes.
            [Description("This argument is a ParamArray")]
            params int[] args)
        {}
    }

    class DemoClass {
        static void Main(string[] args) {
            // Get the Class type to access its metadata.
            Type clsType = typeof(AClass);
            // Get the type information for the method.
            MethodInfo mInfo = clsType.GetMethod("ParamArrayAndDesc");
            if (mInfo != null) {
                // Get the parameter information.
                ParameterInfo[] pInfo = mInfo.GetParameters();
                if (pInfo != null) {
                    // Iterate through all the attributes for the parameter.
                    foreach(Attribute attr in 
                        Attribute.GetCustomAttributes(pInfo[0])) {
                        // Check for the ParamArray attribute.
                        if (attr.GetType() == typeof(ParamArrayAttribute))
                            Console.WriteLine("Parameter {0} for method {1} " +
                                "has the ParamArray attribute.",
                                pInfo[0].Name, mInfo.Name);
                        // Check for the Description attribute.
                        else if (attr.GetType() == 
                            typeof(DescriptionAttribute)) {
                            Console.WriteLine("Parameter {0} for method {1} " +
                                "has a description attribute.",
                                pInfo[0].Name, mInfo.Name);
                            Console.WriteLine("The description is: \"{0}\"",
                                ((DescriptionAttribute)attr).Description);
                        }
                    }
                }
            }
        }
    }
}

/*
 * Output:
 * Parameter args for method ParamArrayAndDesc has a description attribute.
 * The description is: "This argument is a ParamArray"
 * Parameter args for method ParamArrayAndDesc has the ParamArray attribute.
 */
Imports System.Reflection
Imports System.ComponentModel

Module DemoModule
    Public Class AClass
        ' Add Description and ParamArray (with the keyword) attributes.
        Public Sub ParamArrayAndDesc( _
            <Description("This argument is a ParamArray")> _
            ByVal ParamArray args() As Integer)
        End Sub
    End Class

    Sub Main()
        ' Get the Class type to access its metadata.
        Dim clsType As Type = GetType(AClass)
        ' Get the type information for the method.
        Dim mInfo As MethodInfo = clsType.GetMethod("ParamArrayAndDesc")
        ' Get the Parameter information for the method.
        Dim pInfo() As ParameterInfo = mInfo.GetParameters()
        Dim attr As Attribute
        ' Iterate through each attribute of the parameter.
        For Each attr In Attribute.GetCustomAttributes(pInfo(0))
            ' Check for the ParamArray attribute.
            If TypeOf attr Is ParamArrayAttribute Then
                ' Convert the attribute to access its data.
                Dim paAttr As ParamArrayAttribute = _
                    CType(attr, ParamArrayAttribute)
                Console.WriteLine("Parameter {0} has the " + _
                    "ParamArray attribute.", pInfo(0).Name)
            ' Check for the Description attribute.
            ElseIf TypeOf attr Is DescriptionAttribute Then
                ' Convert the attribute to access its data.
                Dim descAttr As DescriptionAttribute = _
                    CType(attr, DescriptionAttribute)
                Console.WriteLine("Parameter {0} has a description " + _
                    "attribute. The description is:", pInfo(0).Name)
                Console.WriteLine(descAttr.Description)
            End If
        Next
    End Sub
End Module

' Output:
' Parameter args has a description attribute. The description is:
' This argument is a ParamArray
' Parameter args has the ParamArray attribute.

注解

如果 element 表示派生类型的方法中的参数,则返回值包括应用于重写的基方法中的相同参数的可继承自定义特性。If element represents a parameter in a method of a derived type, the return value includes the inheritable custom attributes applied to the same parameter in the overridden base methods.

GetCustomAttributes(Module, Boolean)

检索应用于模块的自定义属性的数组。Retrieves an array of the custom attributes applied to a module. 参数指定模块及忽略的搜索选项。Parameters specify the module, and an ignored search option.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::Module ^ element, bool inherit);
public static Attribute[] GetCustomAttributes (System.Reflection.Module element, bool inherit);
static member GetCustomAttributes : System.Reflection.Module * bool -> Attribute[]
Public Shared Function GetCustomAttributes (element As Module, inherit As Boolean) As Attribute()

参数

element
Module

一个从 Module 类派生的对象,该类描述可移植的可执行文件。An object derived from the Module class that describes a portable executable file.

inherit
Boolean

此参数被忽略,并且不会影响此方法的操作。This parameter is ignored, and does not affect the operation of this method.

返回

一个 Attribute 数组,其中包含应用于 element 的自定义属性;如果不存在任何此类自定义属性,则为空数组。An Attribute array that contains the custom attributes applied to element, or an empty array if no such custom attributes exist.

异常

elementattributeTypenullelement or attributeType is null.

示例

下面的代码示例演示如何使用 GetCustomAttributes,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttributes, taking a Module as a parameter.

using namespace System;
using namespace System::Reflection;
using namespace System::ComponentModel;

// Assign some attributes to the module.
// Set the module's CLSCompliant attribute to false
// The CLSCompliant attribute is applicable for /target:module.
[module:Description("A sample description")];
[module:CLSCompliant(false)];
namespace CustAttrs2CS
{
   ref class DemoClass
   {
   public:
      static void Main()
      {
         Type^ clsType = DemoClass::typeid;

         // Get the Module type to access its metadata.
         Module^ module = clsType->Module;

         // Iterate through all the attributes for the module.
         System::Collections::IEnumerator^ myEnum1 = Attribute::GetCustomAttributes( module )->GetEnumerator();
         while ( myEnum1->MoveNext() )
         {
            Attribute^ attr = safe_cast<Attribute^>(myEnum1->Current);

            // Check for the Description attribute.
            if ( attr->GetType() == DescriptionAttribute::typeid )
                        Console::WriteLine( "Module {0} has the description \"{1}\".", module->Name, (dynamic_cast<DescriptionAttribute^>(attr))->Description );
            // Check for the CLSCompliant attribute.
            else

            // Check for the CLSCompliant attribute.
            if ( attr->GetType() == CLSCompliantAttribute::typeid )
                        Console::WriteLine( "Module {0} {1} CLSCompliant.", module->Name, (dynamic_cast<CLSCompliantAttribute^>(attr))->IsCompliant ? (String^)"is" : "is not" );
         }
      }
   };
}


/*
 * Output:
 * Module CustAttrs2CS.exe is not CLSCompliant.
 * Module CustAttrs2CS.exe has the description "A sample description".
 */
using System;
using System.Reflection;
using System.ComponentModel;

// Assign some attributes to the module.
[module:Description("A sample description")]

// Set the module's CLSCompliant attribute to false
// The CLSCompliant attribute is applicable for /target:module.
[module:CLSCompliant(false)]

namespace CustAttrs2CS {
    class DemoClass {
        static void Main(string[] args) {
            Type clsType = typeof(DemoClass);
            // Get the Module type to access its metadata.
            Module module = clsType.Module;

            // Iterate through all the attributes for the module.
            foreach(Attribute attr in Attribute.GetCustomAttributes(module)) {
                // Check for the Description attribute.
                if (attr.GetType() == typeof(DescriptionAttribute))
                    Console.WriteLine("Module {0} has the description " +
                        "\"{1}\".", module.Name, 
                        ((DescriptionAttribute)attr).Description);
                // Check for the CLSCompliant attribute.
                else if (attr.GetType() == typeof(CLSCompliantAttribute))
                    Console.WriteLine("Module {0} {1} CLSCompliant.",
                        module.Name,
                        ((CLSCompliantAttribute)attr).IsCompliant ? 
                            "is" : "is not");
            }
        }
    }
}

/*
 * Output:
 * Module CustAttrs2CS.exe is not CLSCompliant.
 * Module CustAttrs2CS.exe has the description "A sample description".
 */
Imports System.Reflection
Imports System.ComponentModel

' Give the Module some attributes.
<Module: Description("A sample description")> 

' Make the CLSCompliant attribute False.
' The CLSCompliant attribute is applicable for /target:module.
<Module: CLSCompliant(False)> 

Module DemoModule

    Sub Main()
        ' Get the Module type to access its metadata.
        Dim modType As Reflection.Module = GetType(DemoModule).Module
        Dim attr As Attribute
        ' Iterate through all the attributes for the module.
        For Each attr In Attribute.GetCustomAttributes(modType)
            ' Check for the Description attribute.
            If TypeOf attr Is DescriptionAttribute Then
                ' Convert the attribute to access its data.
                Dim descAttr As DescriptionAttribute = _
                    CType(attr, DescriptionAttribute)
                Console.WriteLine("Module {0} has the description ""{1}"".", _
                    modType.Name, descAttr.Description)

            ' Check for the CLSCompliant attribute.
            ElseIf TypeOf attr Is CLSCompliantAttribute Then
                ' Convert the attribute to access its data.
                Dim CLSCompAttr As CLSCompliantAttribute = _
                    CType(attr, CLSCompliantAttribute)
                Dim strCompliant As String
                If CLSCompAttr.IsCompliant Then
                    strCompliant = "is"
                Else
                    strCompliant = "is not"
                End If
                Console.WriteLine("Module {0} {1} CLSCompliant.", _
                    modType.Name, strCompliant)
            End If
        Next
    End Sub
End Module

' Output:
' Module CustAttrs2VB.exe has the description "A sample description".
' Module CustAttrs2VB.exe is not CLSCompliant.

注解

如果 inherit @no__t 为-2,则返回值将包含 element 的祖先的自定义属性。The return value contains the custom attributes for ancestors of element if inherit is true.

GetCustomAttributes(ParameterInfo, Boolean)

检索应用于方法参数的自定义属性的数组。Retrieves an array of the custom attributes applied to a method parameter. 参数指定方法参数以及是否搜索方法参数的祖先。Parameters specify the method parameter, and whether to search ancestors of the method parameter.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::ParameterInfo ^ element, bool inherit);
public static Attribute[] GetCustomAttributes (System.Reflection.ParameterInfo element, bool inherit);
static member GetCustomAttributes : System.Reflection.ParameterInfo * bool -> Attribute[]
Public Shared Function GetCustomAttributes (element As ParameterInfo, inherit As Boolean) As Attribute()

参数

element
ParameterInfo

一个从 ParameterInfo 类派生的对象,该类描述类成员的参数。An object derived from the ParameterInfo class that describes a parameter of a member of a class.

inherit
Boolean

如果为 true,则指定还在 element 的祖先中搜索自定义属性。If true, specifies to also search the ancestors of element for custom attributes.

返回

一个 Attribute 数组,其中包含应用于 element 的自定义属性;如果不存在任何此类自定义属性,则为空数组。An Attribute array that contains the custom attributes applied to element, or an empty array if no such custom attributes exist.

异常

elementMember 属性为 nullThe Member property of element is null.

elementnullelement is null.

无法加载自定义属性类型。A custom attribute type cannot be loaded.

示例

下面的代码示例演示如何使用 GetCustomAttributes,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttributes, taking a ParameterInfo as a parameter.

using namespace System;
using namespace System::Reflection;
using namespace System::ComponentModel;

namespace CustAttrs5CS
{
   public ref class AClass
   {
   public:
      void ParamArrayAndDesc(
         // Add ParamArray and Description attributes.
         [Description("This argument is a ParamArray")]
         array<Int32>^args )
      {}
   };

   ref class DemoClass
   {
   public:
      static void Main()
      {
         // Get the Class type to access its metadata.
         Type^ clsType = AClass::typeid;

         // Get the type information for the method.
         MethodInfo^ mInfo = clsType->GetMethod( "ParamArrayAndDesc" );
         if ( mInfo != nullptr )
         {
            // Get the parameter information.
            array<ParameterInfo^>^pInfo = mInfo->GetParameters();
            if ( pInfo != nullptr )
            {
               // Iterate through all the attributes for the parameter.
               System::Collections::IEnumerator^ myEnum4 = Attribute::GetCustomAttributes( pInfo[ 0 ] )->GetEnumerator();
               while ( myEnum4->MoveNext() )
               {
                  Attribute^ attr = safe_cast<Attribute^>(myEnum4->Current);

                  // Check for the ParamArray attribute.
                  if ( attr->GetType() == ParamArrayAttribute::typeid )
                                    Console::WriteLine( "Parameter {0} for method {1} "
                  "has the ParamArray attribute.", pInfo[ 0 ]->Name, mInfo->Name );
                  // Check for the Description attribute.
                  else

                  // Check for the Description attribute.
                  if ( attr->GetType() == DescriptionAttribute::typeid )
                  {
                     Console::WriteLine( "Parameter {0} for method {1} "
                     "has a description attribute.", pInfo[ 0 ]->Name, mInfo->Name );
                     Console::WriteLine( "The description is: \"{0}\"", (dynamic_cast<DescriptionAttribute^>(attr))->Description );
                  }
               }
            }
         }
      }
   };
}

/*
 * Output:
 * Parameter args for method ParamArrayAndDesc has a description attribute.
 * The description is: "This argument is a ParamArray"
 * Parameter args for method ParamArrayAndDesc has the ParamArray attribute.
 */
using System;
using System.Reflection;
using System.ComponentModel;

namespace CustAttrs5CS {
    public class AClass {
        public void ParamArrayAndDesc(
            // Add ParamArray (with the keyword) and Description attributes.
            [Description("This argument is a ParamArray")]
            params int[] args)
        {}
    }

    class DemoClass {
        static void Main(string[] args) {
            // Get the Class type to access its metadata.
            Type clsType = typeof(AClass);
            // Get the type information for the method.
            MethodInfo mInfo = clsType.GetMethod("ParamArrayAndDesc");
            if (mInfo != null) {
                // Get the parameter information.
                ParameterInfo[] pInfo = mInfo.GetParameters();
                if (pInfo != null) {
                    // Iterate through all the attributes for the parameter.
                    foreach(Attribute attr in 
                        Attribute.GetCustomAttributes(pInfo[0])) {
                        // Check for the ParamArray attribute.
                        if (attr.GetType() == typeof(ParamArrayAttribute))
                            Console.WriteLine("Parameter {0} for method {1} " +
                                "has the ParamArray attribute.",
                                pInfo[0].Name, mInfo.Name);
                        // Check for the Description attribute.
                        else if (attr.GetType() == 
                            typeof(DescriptionAttribute)) {
                            Console.WriteLine("Parameter {0} for method {1} " +
                                "has a description attribute.",
                                pInfo[0].Name, mInfo.Name);
                            Console.WriteLine("The description is: \"{0}\"",
                                ((DescriptionAttribute)attr).Description);
                        }
                    }
                }
            }
        }
    }
}

/*
 * Output:
 * Parameter args for method ParamArrayAndDesc has a description attribute.
 * The description is: "This argument is a ParamArray"
 * Parameter args for method ParamArrayAndDesc has the ParamArray attribute.
 */
Imports System.Reflection
Imports System.ComponentModel

Module DemoModule
    Public Class AClass
        ' Add Description and ParamArray (with the keyword) attributes.
        Public Sub ParamArrayAndDesc( _
            <Description("This argument is a ParamArray")> _
            ByVal ParamArray args() As Integer)
        End Sub
    End Class

    Sub Main()
        ' Get the Class type to access its metadata.
        Dim clsType As Type = GetType(AClass)
        ' Get the type information for the method.
        Dim mInfo As MethodInfo = clsType.GetMethod("ParamArrayAndDesc")
        ' Get the Parameter information for the method.
        Dim pInfo() As ParameterInfo = mInfo.GetParameters()
        Dim attr As Attribute
        ' Iterate through each attribute of the parameter.
        For Each attr In Attribute.GetCustomAttributes(pInfo(0))
            ' Check for the ParamArray attribute.
            If TypeOf attr Is ParamArrayAttribute Then
                ' Convert the attribute to access its data.
                Dim paAttr As ParamArrayAttribute = _
                    CType(attr, ParamArrayAttribute)
                Console.WriteLine("Parameter {0} has the " + _
                    "ParamArray attribute.", pInfo(0).Name)
            ' Check for the Description attribute.
            ElseIf TypeOf attr Is DescriptionAttribute Then
                ' Convert the attribute to access its data.
                Dim descAttr As DescriptionAttribute = _
                    CType(attr, DescriptionAttribute)
                Console.WriteLine("Parameter {0} has a description " + _
                    "attribute. The description is:", pInfo(0).Name)
                Console.WriteLine(descAttr.Description)
            End If
        Next
    End Sub
End Module

' Output:
' Parameter args has a description attribute. The description is:
' This argument is a ParamArray
' Parameter args has the ParamArray attribute.

注解

如果 element 表示派生类型的方法中的参数,则返回值包括应用于重写的基方法中的相同参数的可继承自定义特性。If element represents a parameter in a method of a derived type, the return value includes the inheritable custom attributes applied to the same parameter in the overridden base methods.

GetCustomAttributes(MemberInfo, Boolean)

检索应用于类型的成员的自定义属性的数组。Retrieves an array of the custom attributes applied to a member of a type. 参数指定成员、要搜索的自定义属性的类型以及是否搜索成员的祖先。Parameters specify the member, the type of the custom attribute to search for, and whether to search ancestors of the member.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::MemberInfo ^ element, bool inherit);
public static Attribute[] GetCustomAttributes (System.Reflection.MemberInfo element, bool inherit);
static member GetCustomAttributes : System.Reflection.MemberInfo * bool -> Attribute[]
Public Shared Function GetCustomAttributes (element As MemberInfo, inherit As Boolean) As Attribute()

参数

element
MemberInfo

一个从 MemberInfo 类派生的对象,该类描述类的构造函数、事件、字段、方法或属性成员。An object derived from the MemberInfo class that describes a constructor, event, field, method, or property member of a class.

inherit
Boolean

如果为 true,则指定还在 element 的祖先中搜索自定义属性。If true, specifies to also search the ancestors of element for custom attributes.

返回

一个 Attribute 数组,其中包含应用于 element 的自定义属性;如果不存在任何此类自定义属性,则为空数组。An Attribute array that contains the custom attributes applied to element, or an empty array if no such custom attributes exist.

异常

elementnullelement is null.

element 不是构造函数、方法、属性、事件、类型或字段。element is not a constructor, method, property, event, type, or field.

无法加载自定义属性类型。A custom attribute type cannot be loaded.

示例

下面的代码示例演示如何使用 GetCustomAttributes,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttributes, taking a MemberInfo as a parameter.

using namespace System;
using namespace System::Reflection;
using namespace System::Security;
using namespace System::Runtime::InteropServices;

namespace CustAttrs4CS
{
   // Create a class for Win32 imported unmanaged functions.
   public ref class Win32
   {
   public:

      [DllImport("user32.dll", CharSet = CharSet::Unicode)]
      static int MessageBox( int hWnd, String^ text, String^ caption, UInt32 type );
   };

   public ref class AClass
   {
   public:

      // Add some attributes to the Win32CallMethod.

      [Obsolete("This method is obsolete. Use managed MsgBox instead.")]
      void Win32CallMethod()
      {
         Win32::MessageBox( 0, "This is an unmanaged call.", "Be Careful!", 0 );
      }

   };

   ref class DemoClass
   {
   public:
      static void Main()
      {
         // Get the Class type to access its metadata.
         Type^ clsType = AClass::typeid;

         // Get the type information for the Win32CallMethod.
         MethodInfo^ mInfo = clsType->GetMethod( "Win32CallMethod" );
         if ( mInfo != nullptr )
         {
            // Iterate through all the attributes for the method.
            System::Collections::IEnumerator^ myEnum3 = Attribute::GetCustomAttributes( mInfo )->GetEnumerator();
            while ( myEnum3->MoveNext() )
            {
               Attribute^ attr = safe_cast<Attribute^>(myEnum3->Current);

               // Check for the Obsolete attribute.
               if ( attr->GetType() == ObsoleteAttribute::typeid )
               {
                  Console::WriteLine( "Method {0} is obsolete. "
                  "The message is:", mInfo->Name );
                  Console::WriteLine( (dynamic_cast<ObsoleteAttribute^>(attr))->Message );
               }
               // Check for the SuppressUnmanagedCodeSecurity attribute.
               else

               // Check for the SuppressUnmanagedCodeSecurity attribute.
               if ( attr->GetType() == SuppressUnmanagedCodeSecurityAttribute::typeid )
               {
                  Console::WriteLine( "This method calls unmanaged code "
                  "with no security check." );
                  Console::WriteLine( "Please do not use unless absolutely necessary." );
                  AClass^ myCls = gcnew AClass;
                  myCls->Win32CallMethod();
               }
            }
         }
      }
   };
}


/*
 * Output:
 * Method Win32CallMethod is obsolete. The message is:
 * This method is obsolete. Use managed MsgBox instead.
 * This method calls unmanaged code with no security check.
 * Please do not use unless absolutely necessary.
 */
using System;
using System.Reflection;
using System.Security;
using System.Runtime.InteropServices;

namespace CustAttrs4CS
{

    // Define an enumeration of Win32 unmanaged types
    public enum UnmanagedType
    {
        User,
        GDI,
        Kernel,
        Shell,
        Networking,
        Multimedia
    }

    // Define the Unmanaged attribute.
    public class UnmanagedAttribute : Attribute
    {
        // Storage for the UnmanagedType value.
        protected UnmanagedType thisType;

        // Set the unmanaged type in the constructor.
        public UnmanagedAttribute(UnmanagedType type)
        {
            thisType = type;
        }

        // Define a property to get and set the UnmanagedType value.
        public UnmanagedType Win32Type
        {
            get { return thisType; }
            set { thisType = Win32Type; }
        }
    }

    // Create a class for an imported Win32 unmanaged function.
    public class Win32 {
        [DllImport("user32.dll", CharSet = CharSet.Unicode)]
        public static extern int MessageBox(int hWnd, String text,
            String caption, uint type);
    }

    public class AClass {
        // Add some attributes to Win32CallMethod.
        [Obsolete("This method is obsolete. Use managed MsgBox instead.")]
        [Unmanaged(UnmanagedType.User)]
        public void Win32CallMethod()
        {
            Win32.MessageBox(0, "This is an unmanaged call.", "Caution!", 0);
        }
    }

    class DemoClass {
        static void Main(string[] args)
            {
            // Get the AClass type to access its metadata.
            Type clsType = typeof(AClass);
            // Get the type information for Win32CallMethod.
            MethodInfo mInfo = clsType.GetMethod("Win32CallMethod");
            if (mInfo != null)
            {
                // Iterate through all the attributes of the method.
                foreach(Attribute attr in
                    Attribute.GetCustomAttributes(mInfo)) {
                    // Check for the Obsolete attribute.
                    if (attr.GetType() == typeof(ObsoleteAttribute))
                    {
                        Console.WriteLine("Method {0} is obsolete. " +
                            "The message is:",
                            mInfo.Name);
                        Console.WriteLine("  \"{0}\"",
                            ((ObsoleteAttribute)attr).Message);
                    }

                    // Check for the Unmanaged attribute.
                    else if (attr.GetType() == typeof(UnmanagedAttribute))
                    {
                        Console.WriteLine(
                            "This method calls unmanaged code.");
                        Console.WriteLine(
                            String.Format("The Unmanaged attribute type is {0}.",
                                          ((UnmanagedAttribute)attr).Win32Type));
                        AClass myCls = new AClass();
                        myCls.Win32CallMethod();
                    }
                }
            }
        }
    }
}

/*

This code example produces the following results.

First, the compilation yields the warning, "...This method is
obsolete. Use managed MsgBox instead."
Second, execution yields a message box with a title of "Caution!"
and message text of "This is an unmanaged call."
Third, the following text is displayed in the console window:

Method Win32CallMethod is obsolete. The message is:
  "This method is obsolete. Use managed MsgBox instead."
This method calls unmanaged code.
The Unmanaged attribute type is User.

*/

Imports System.Reflection
Imports System.Security
Imports System.Runtime.InteropServices

' Define an enumeration of Win32 unmanaged types
Public Enum UnmanagedType
    User
    GDI
    Kernel
    Shell
    Networking
    Multimedia
End Enum 'UnmanagedType

' Define the Unmanaged attribute.
Public Class UnmanagedAttribute 
             Inherits Attribute

    ' Storage for the UnmanagedType value.
    Protected thisType As UnmanagedType
    
    ' Set the unmanaged type in the constructor.
    Public Sub New(ByVal type As UnmanagedType) 
        thisType = type
    End Sub
    
    ' Define a property to get and set the UnmanagedType value.
    Public Property Win32Type() As UnmanagedType 
        Get
            Return thisType
        End Get
        Set
            thisType = Win32Type
        End Set
    End Property
End Class

' Create a class for an imported Win32 unmanaged function.
Public Class Win32
    <DllImport("user32.dll", CharSet:=CharSet.Unicode)> _
    Public Shared Function MessageBox(ByVal hWnd As Integer, _
                                      ByVal Text As String, _
                                      ByVal caption As String, _
                                      ByVal type As Integer) As Integer
    End Function 'MessageBox
End Class

Public Class AClass
    ' Add some attributes to Win32CallMethod.
    <Obsolete("This method is obsolete. Use managed MsgBox instead."), _
     Unmanaged(UnmanagedType.User)>  _
    Public Sub Win32CallMethod() 
        Win32.MessageBox(0, "This is an unmanaged call.", "Caution!", 0)    
    End Sub
End Class

Class DemoClass
    Shared Sub Main(ByVal args() As String) 
        ' Get the AClass type to access its metadata.
        Dim clsType As Type = GetType(AClass)
        ' Get the type information for Win32CallMethod.
        Dim mInfo As MethodInfo = clsType.GetMethod("Win32CallMethod")
        If Not (mInfo Is Nothing) Then
            ' Iterate through all the attributes of the method.
            Dim attr As Attribute
            For Each attr In  Attribute.GetCustomAttributes(mInfo)
                ' Check for the Obsolete attribute.
                If attr.GetType().Equals(GetType(ObsoleteAttribute)) Then
                    Console.WriteLine("Method {0} is obsolete. The message is:", mInfo.Name)
                    Console.WriteLine("  ""{0}""", CType(attr, ObsoleteAttribute).Message)
                ' Check for the Unmanaged attribute.
                ElseIf attr.GetType().Equals(GetType(UnmanagedAttribute)) Then
                    Console.WriteLine("This method calls unmanaged code.")
                    Console.WriteLine( _
                            String.Format("The Unmanaged attribute type is {0}.", _
                            CType(attr, UnmanagedAttribute).Win32Type))
                    Dim myCls As New AClass()
                    myCls.Win32CallMethod()
                End If
            Next attr
        End If
    End Sub
End Class

'
'This code example produces the following results. 
'
'First, the compilation yields the warning, "...This method is 
'obsolete. Use managed MsgBox instead."
'Second, execution yields a message box with a title of "Caution!" 
'and message text of "This is an unmanaged call." 
'Third, the following text is displayed in the console window:
'
'Method Win32CallMethod is obsolete. The message is:
'  "This method is obsolete. Use managed MsgBox instead."
'This method calls unmanaged code.
'The Unmanaged attribute type is User.
' 

注解

如果 inherit @no__t 为-2,则返回值将包含 element 的祖先的自定义属性。The return value contains the custom attributes for ancestors of element if inherit is true.

备注

从 .NET Framework 版本2.0 开始,如果属性以新的元数据格式存储,则此方法将返回方法、构造函数和类型的安全特性。Starting with the .NET Framework version 2.0, this method returns security attributes on methods, constructors, and types if the attributes are stored in the new metadata format. 使用版本2.0 或更高版本编译的程序集将使用新的格式。Assemblies compiled with version 2.0 or later use the new format. 使用早期版本的 .NET Framework 编译的动态程序集和程序集使用旧的 XML 格式。Dynamic assemblies and assemblies compiled with earlier versions of the .NET Framework use the old XML format. 请参阅发出声明性安全特性See Emitting Declarative Security Attributes.

GetCustomAttributes(Assembly, Type)

检索一个数组,它由应用于程序集的自定义属性组成。Retrieves an array of the custom attributes applied to an assembly. 参数指定程序集和要搜索的自定义属性的类型。Parameters specify the assembly, and the type of the custom attribute to search for.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::Assembly ^ element, Type ^ attributeType);
public static Attribute[] GetCustomAttributes (System.Reflection.Assembly element, Type attributeType);
static member GetCustomAttributes : System.Reflection.Assembly * Type -> Attribute[]
Public Shared Function GetCustomAttributes (element As Assembly, attributeType As Type) As Attribute()

参数

element
Assembly

一个派生自 Assembly 类的对象,用于描述模块的可重用集合。An object derived from the Assembly class that describes a reusable collection of modules.

attributeType
Type

要搜索的自定义属性的类型或基类型。The type, or a base type, of the custom attribute to search for.

返回

一个 Attribute 数组,包含应用于 attributeTypeelement 类型的自定义属性;如果不存在此类自定义属性,则为空数组。An Attribute array that contains the custom attributes of type attributeType applied to element, or an empty array if no such custom attributes exist.

异常

elementattributeTypenullelement or attributeType is null.

attributeType 不是从 Attribute 派生的。attributeType is not derived from Attribute.

示例

下面的代码示例演示如何使用 GetCustomAttributes,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttributes, taking an Assembly as a parameter.

using namespace System;
using namespace System::Reflection;

[assembly:AssemblyTitle("CustAttrs1CPP")];
[assembly:AssemblyDescription("GetCustomAttributes() Demo")];
[assembly:AssemblyCompany("Microsoft")];

ref class Example
{};

static void main()
{
    Type^ clsType = Example::typeid;

    // Get the Assembly type to access its metadata.
    Assembly^ assy = clsType->Assembly;

    // Iterate through the attributes for the assembly.
    System::Collections::IEnumerator^ myEnum = Attribute::GetCustomAttributes( assy )->GetEnumerator();
    while ( myEnum->MoveNext() )
    {
       Attribute^ attr = safe_cast<Attribute^>(myEnum->Current);

       // Check for the AssemblyTitle attribute.
       if ( attr->GetType() == AssemblyTitleAttribute::typeid )
          Console::WriteLine( "Assembly title is \"{0}\".", (dynamic_cast<AssemblyTitleAttribute^>(attr))->Title );
          // Check for the AssemblyDescription attribute.
       else
          // Check for the AssemblyDescription attribute.
          if ( attr->GetType() == AssemblyDescriptionAttribute::typeid )
             Console::WriteLine( "Assembly description is \"{0}\".", (dynamic_cast<AssemblyDescriptionAttribute^>(attr))->Description );
          // Check for the AssemblyCompany attribute.
          else if ( attr->GetType() == AssemblyCompanyAttribute::typeid )
             Console::WriteLine( "Assembly company is {0}.", (dynamic_cast<AssemblyCompanyAttribute^>(attr))->Company );
    }
}
// The example displays the following output:
//     Assembly description is "GetCustomAttributes() Demo".
//     Assembly company is Microsoft.
//     Assembly title is "CustAttrs1CPP".
using System;
using System.Reflection;

[assembly: AssemblyTitle("CustAttrs1CS")]
[assembly: AssemblyDescription("GetCustomAttributes() Demo")]
[assembly: AssemblyCompany("Microsoft")]

class Example {
    static void Main() {
        // Get the Assembly object to access its metadata.
        Assembly assy = typeof(Example).Assembly;

        // Iterate through the attributes for the assembly.
        foreach(Attribute attr in Attribute.GetCustomAttributes(assy)) {
            // Check for the AssemblyTitle attribute.
            if (attr.GetType() == typeof(AssemblyTitleAttribute))
                Console.WriteLine("Assembly title is \"{0}\".",
                    ((AssemblyTitleAttribute)attr).Title);

            // Check for the AssemblyDescription attribute.
            else if (attr.GetType() == 
                typeof(AssemblyDescriptionAttribute))
                Console.WriteLine("Assembly description is \"{0}\".",
                    ((AssemblyDescriptionAttribute)attr).Description);

            // Check for the AssemblyCompany attribute.
            else if (attr.GetType() == typeof(AssemblyCompanyAttribute))
                Console.WriteLine("Assembly company is {0}.",
                    ((AssemblyCompanyAttribute)attr).Company);
        }
   }
}
// The example displays the following output:
//     Assembly title is "CustAttrs1CS".
//     Assembly description is "GetCustomAttributes() Demo".
//     Assembly company is Microsoft.
Imports System.Reflection

<Assembly: AssemblyTitle("CustAttrs1VB")> 
<Assembly: AssemblyDescription("GetCustomAttributes() Demo")> 
<Assembly: AssemblyCompany("Microsoft")> 

Module Example
    Sub Main()
        ' Get the Assembly type to access its metadata.
        Dim assy As Reflection.Assembly = GetType(Example).Assembly

        ' Iterate through all the attributes for the assembly.
        For Each attr As Attribute In Attribute.GetCustomAttributes(assy)
            ' Check for the AssemblyTitle attribute.
            If TypeOf attr Is AssemblyTitleAttribute Then
                ' Convert the attribute to access its data.
                Dim attrTitle As AssemblyTitleAttribute = _
                    CType(attr, AssemblyTitleAttribute)
                Console.WriteLine("Assembly title is ""{0}"".", _
                    attrTitle.Title)

            ' Check for the AssemblyDescription attribute.
            ElseIf TypeOf attr Is AssemblyDescriptionAttribute Then
                ' Convert the attribute to access its data.
                Dim attrDesc As AssemblyDescriptionAttribute = _
                    CType(attr, AssemblyDescriptionAttribute)
                Console.WriteLine("Assembly description is ""{0}"".", _
                    attrDesc.Description)

            ' Check for the AssemblyCompany attribute.
            ElseIf TypeOf attr Is AssemblyCompanyAttribute Then
                ' Convert the attribute to access its data.
                Dim attrComp As AssemblyCompanyAttribute = _
                    CType(attr, AssemblyCompanyAttribute)
                Console.WriteLine("Assembly company is {0}.", _
                    attrComp.Company)
            End If
        Next
    End Sub
End Module
' The example displays the following output:
'     Assembly company is Microsoft.
'     Assembly description is "GetCustomAttributes() Demo".
'     Assembly title is "CustAttrs1VB".

注解

备注

从 .NET Framework 版本2.0 开始,如果属性以新的元数据格式存储,则此方法返回安全特性。Starting with the .NET Framework version 2.0, this method returns security attributes if the attributes are stored in the new metadata format. 使用版本2.0 或更高版本编译的程序集将使用新的格式。Assemblies compiled with version 2.0 or later use the new format. 使用早期版本的 .NET Framework 编译的动态程序集和程序集使用旧的 XML 格式。Dynamic assemblies and assemblies compiled with earlier versions of the .NET Framework use the old XML format. 请参阅发出声明性安全特性See Emitting Declarative Security Attributes.

GetCustomAttributes(Assembly, Boolean)

检索一个数组,它由应用于程序集的自定义属性组成。Retrieves an array of the custom attributes applied to an assembly. 参数指定程序集及忽略的搜索选项。Parameters specify the assembly, and an ignored search option.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::Assembly ^ element, bool inherit);
public static Attribute[] GetCustomAttributes (System.Reflection.Assembly element, bool inherit);
static member GetCustomAttributes : System.Reflection.Assembly * bool -> Attribute[]
Public Shared Function GetCustomAttributes (element As Assembly, inherit As Boolean) As Attribute()

参数

element
Assembly

一个派生自 Assembly 类的对象,用于描述模块的可重用集合。An object derived from the Assembly class that describes a reusable collection of modules.

inherit
Boolean

此参数被忽略,并且不会影响此方法的操作。This parameter is ignored, and does not affect the operation of this method.

返回

一个 Attribute 数组,其中包含应用于 element 的自定义属性;如果不存在任何此类自定义属性,则为空数组。An Attribute array that contains the custom attributes applied to element, or an empty array if no such custom attributes exist.

异常

elementattributeTypenullelement or attributeType is null.

示例

下面的代码示例演示如何使用 GetCustomAttributes,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttributes, taking an Assembly as a parameter.

using namespace System;
using namespace System::Reflection;

[assembly:AssemblyTitle("CustAttrs1CPP")];
[assembly:AssemblyDescription("GetCustomAttributes() Demo")];
[assembly:AssemblyCompany("Microsoft")];

ref class Example
{};

static void main()
{
    Type^ clsType = Example::typeid;

    // Get the Assembly type to access its metadata.
    Assembly^ assy = clsType->Assembly;

    // Iterate through the attributes for the assembly.
    System::Collections::IEnumerator^ myEnum = Attribute::GetCustomAttributes( assy )->GetEnumerator();
    while ( myEnum->MoveNext() )
    {
       Attribute^ attr = safe_cast<Attribute^>(myEnum->Current);

       // Check for the AssemblyTitle attribute.
       if ( attr->GetType() == AssemblyTitleAttribute::typeid )
          Console::WriteLine( "Assembly title is \"{0}\".", (dynamic_cast<AssemblyTitleAttribute^>(attr))->Title );
          // Check for the AssemblyDescription attribute.
       else
          // Check for the AssemblyDescription attribute.
          if ( attr->GetType() == AssemblyDescriptionAttribute::typeid )
             Console::WriteLine( "Assembly description is \"{0}\".", (dynamic_cast<AssemblyDescriptionAttribute^>(attr))->Description );
          // Check for the AssemblyCompany attribute.
          else if ( attr->GetType() == AssemblyCompanyAttribute::typeid )
             Console::WriteLine( "Assembly company is {0}.", (dynamic_cast<AssemblyCompanyAttribute^>(attr))->Company );
    }
}
// The example displays the following output:
//     Assembly description is "GetCustomAttributes() Demo".
//     Assembly company is Microsoft.
//     Assembly title is "CustAttrs1CPP".
using System;
using System.Reflection;

[assembly: AssemblyTitle("CustAttrs1CS")]
[assembly: AssemblyDescription("GetCustomAttributes() Demo")]
[assembly: AssemblyCompany("Microsoft")]

class Example {
    static void Main() {
        // Get the Assembly object to access its metadata.
        Assembly assy = typeof(Example).Assembly;

        // Iterate through the attributes for the assembly.
        foreach(Attribute attr in Attribute.GetCustomAttributes(assy)) {
            // Check for the AssemblyTitle attribute.
            if (attr.GetType() == typeof(AssemblyTitleAttribute))
                Console.WriteLine("Assembly title is \"{0}\".",
                    ((AssemblyTitleAttribute)attr).Title);

            // Check for the AssemblyDescription attribute.
            else if (attr.GetType() == 
                typeof(AssemblyDescriptionAttribute))
                Console.WriteLine("Assembly description is \"{0}\".",
                    ((AssemblyDescriptionAttribute)attr).Description);

            // Check for the AssemblyCompany attribute.
            else if (attr.GetType() == typeof(AssemblyCompanyAttribute))
                Console.WriteLine("Assembly company is {0}.",
                    ((AssemblyCompanyAttribute)attr).Company);
        }
   }
}
// The example displays the following output:
//     Assembly title is "CustAttrs1CS".
//     Assembly description is "GetCustomAttributes() Demo".
//     Assembly company is Microsoft.
Imports System.Reflection

<Assembly: AssemblyTitle("CustAttrs1VB")> 
<Assembly: AssemblyDescription("GetCustomAttributes() Demo")> 
<Assembly: AssemblyCompany("Microsoft")> 

Module Example
    Sub Main()
        ' Get the Assembly type to access its metadata.
        Dim assy As Reflection.Assembly = GetType(Example).Assembly

        ' Iterate through all the attributes for the assembly.
        For Each attr As Attribute In Attribute.GetCustomAttributes(assy)
            ' Check for the AssemblyTitle attribute.
            If TypeOf attr Is AssemblyTitleAttribute Then
                ' Convert the attribute to access its data.
                Dim attrTitle As AssemblyTitleAttribute = _
                    CType(attr, AssemblyTitleAttribute)
                Console.WriteLine("Assembly title is ""{0}"".", _
                    attrTitle.Title)

            ' Check for the AssemblyDescription attribute.
            ElseIf TypeOf attr Is AssemblyDescriptionAttribute Then
                ' Convert the attribute to access its data.
                Dim attrDesc As AssemblyDescriptionAttribute = _
                    CType(attr, AssemblyDescriptionAttribute)
                Console.WriteLine("Assembly description is ""{0}"".", _
                    attrDesc.Description)

            ' Check for the AssemblyCompany attribute.
            ElseIf TypeOf attr Is AssemblyCompanyAttribute Then
                ' Convert the attribute to access its data.
                Dim attrComp As AssemblyCompanyAttribute = _
                    CType(attr, AssemblyCompanyAttribute)
                Console.WriteLine("Assembly company is {0}.", _
                    attrComp.Company)
            End If
        Next
    End Sub
End Module
' The example displays the following output:
'     Assembly company is Microsoft.
'     Assembly description is "GetCustomAttributes() Demo".
'     Assembly title is "CustAttrs1VB".

注解

备注

从 .NET Framework 版本2.0 开始,如果属性以新的元数据格式存储,则此方法返回安全特性。Starting with the .NET Framework version 2.0, this method returns security attributes if the attributes are stored in the new metadata format. 使用版本2.0 或更高版本编译的程序集将使用新的格式。Assemblies compiled with version 2.0 or later use the new format. 使用早期版本的 .NET Framework 编译的动态程序集和程序集使用旧的 XML 格式。Dynamic assemblies and assemblies compiled with earlier versions of the .NET Framework use the old XML format. 请参阅发出声明性安全特性See Emitting Declarative Security Attributes.

GetCustomAttributes(ParameterInfo)

检索应用于方法参数的自定义属性的数组。Retrieves an array of the custom attributes applied to a method parameter. 参数指定方法参数。A parameter specifies the method parameter.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::ParameterInfo ^ element);
public static Attribute[] GetCustomAttributes (System.Reflection.ParameterInfo element);
static member GetCustomAttributes : System.Reflection.ParameterInfo -> Attribute[]
Public Shared Function GetCustomAttributes (element As ParameterInfo) As Attribute()

参数

element
ParameterInfo

一个从 ParameterInfo 类派生的对象,该类描述类成员的参数。An object derived from the ParameterInfo class that describes a parameter of a member of a class.

返回

一个 Attribute 数组,其中包含应用于 element 的自定义属性;如果不存在任何此类自定义属性,则为空数组。An Attribute array that contains the custom attributes applied to element, or an empty array if no such custom attributes exist.

异常

elementnullelement is null.

无法加载自定义属性类型。A custom attribute type cannot be loaded.

示例

下面的代码示例演示如何使用 GetCustomAttributes,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttributes, taking a ParameterInfo as a parameter.

using namespace System;
using namespace System::Reflection;
using namespace System::ComponentModel;

namespace CustAttrs5CS
{
   public ref class AClass
   {
   public:
      void ParamArrayAndDesc(
         // Add ParamArray and Description attributes.
         [Description("This argument is a ParamArray")]
         array<Int32>^args )
      {}
   };

   ref class DemoClass
   {
   public:
      static void Main()
      {
         // Get the Class type to access its metadata.
         Type^ clsType = AClass::typeid;

         // Get the type information for the method.
         MethodInfo^ mInfo = clsType->GetMethod( "ParamArrayAndDesc" );
         if ( mInfo != nullptr )
         {
            // Get the parameter information.
            array<ParameterInfo^>^pInfo = mInfo->GetParameters();
            if ( pInfo != nullptr )
            {
               // Iterate through all the attributes for the parameter.
               System::Collections::IEnumerator^ myEnum4 = Attribute::GetCustomAttributes( pInfo[ 0 ] )->GetEnumerator();
               while ( myEnum4->MoveNext() )
               {
                  Attribute^ attr = safe_cast<Attribute^>(myEnum4->Current);

                  // Check for the ParamArray attribute.
                  if ( attr->GetType() == ParamArrayAttribute::typeid )
                                    Console::WriteLine( "Parameter {0} for method {1} "
                  "has the ParamArray attribute.", pInfo[ 0 ]->Name, mInfo->Name );
                  // Check for the Description attribute.
                  else

                  // Check for the Description attribute.
                  if ( attr->GetType() == DescriptionAttribute::typeid )
                  {
                     Console::WriteLine( "Parameter {0} for method {1} "
                     "has a description attribute.", pInfo[ 0 ]->Name, mInfo->Name );
                     Console::WriteLine( "The description is: \"{0}\"", (dynamic_cast<DescriptionAttribute^>(attr))->Description );
                  }
               }
            }
         }
      }
   };
}

/*
 * Output:
 * Parameter args for method ParamArrayAndDesc has a description attribute.
 * The description is: "This argument is a ParamArray"
 * Parameter args for method ParamArrayAndDesc has the ParamArray attribute.
 */
using System;
using System.Reflection;
using System.ComponentModel;

namespace CustAttrs5CS {
    public class AClass {
        public void ParamArrayAndDesc(
            // Add ParamArray (with the keyword) and Description attributes.
            [Description("This argument is a ParamArray")]
            params int[] args)
        {}
    }

    class DemoClass {
        static void Main(string[] args) {
            // Get the Class type to access its metadata.
            Type clsType = typeof(AClass);
            // Get the type information for the method.
            MethodInfo mInfo = clsType.GetMethod("ParamArrayAndDesc");
            if (mInfo != null) {
                // Get the parameter information.
                ParameterInfo[] pInfo = mInfo.GetParameters();
                if (pInfo != null) {
                    // Iterate through all the attributes for the parameter.
                    foreach(Attribute attr in 
                        Attribute.GetCustomAttributes(pInfo[0])) {
                        // Check for the ParamArray attribute.
                        if (attr.GetType() == typeof(ParamArrayAttribute))
                            Console.WriteLine("Parameter {0} for method {1} " +
                                "has the ParamArray attribute.",
                                pInfo[0].Name, mInfo.Name);
                        // Check for the Description attribute.
                        else if (attr.GetType() == 
                            typeof(DescriptionAttribute)) {
                            Console.WriteLine("Parameter {0} for method {1} " +
                                "has a description attribute.",
                                pInfo[0].Name, mInfo.Name);
                            Console.WriteLine("The description is: \"{0}\"",
                                ((DescriptionAttribute)attr).Description);
                        }
                    }
                }
            }
        }
    }
}

/*
 * Output:
 * Parameter args for method ParamArrayAndDesc has a description attribute.
 * The description is: "This argument is a ParamArray"
 * Parameter args for method ParamArrayAndDesc has the ParamArray attribute.
 */
Imports System.Reflection
Imports System.ComponentModel

Module DemoModule
    Public Class AClass
        ' Add Description and ParamArray (with the keyword) attributes.
        Public Sub ParamArrayAndDesc( _
            <Description("This argument is a ParamArray")> _
            ByVal ParamArray args() As Integer)
        End Sub
    End Class

    Sub Main()
        ' Get the Class type to access its metadata.
        Dim clsType As Type = GetType(AClass)
        ' Get the type information for the method.
        Dim mInfo As MethodInfo = clsType.GetMethod("ParamArrayAndDesc")
        ' Get the Parameter information for the method.
        Dim pInfo() As ParameterInfo = mInfo.GetParameters()
        Dim attr As Attribute
        ' Iterate through each attribute of the parameter.
        For Each attr In Attribute.GetCustomAttributes(pInfo(0))
            ' Check for the ParamArray attribute.
            If TypeOf attr Is ParamArrayAttribute Then
                ' Convert the attribute to access its data.
                Dim paAttr As ParamArrayAttribute = _
                    CType(attr, ParamArrayAttribute)
                Console.WriteLine("Parameter {0} has the " + _
                    "ParamArray attribute.", pInfo(0).Name)
            ' Check for the Description attribute.
            ElseIf TypeOf attr Is DescriptionAttribute Then
                ' Convert the attribute to access its data.
                Dim descAttr As DescriptionAttribute = _
                    CType(attr, DescriptionAttribute)
                Console.WriteLine("Parameter {0} has a description " + _
                    "attribute. The description is:", pInfo(0).Name)
                Console.WriteLine(descAttr.Description)
            End If
        Next
    End Sub
End Module

' Output:
' Parameter args has a description attribute. The description is:
' This argument is a ParamArray
' Parameter args has the ParamArray attribute.

注解

如果 element 表示派生类型的方法中的参数,则返回值包括应用于重写的基方法中的相同参数的可继承自定义特性。If element represents a parameter in a method of a derived type, the return value includes the inheritable custom attributes applied to the same parameter in the overridden base methods.

GetCustomAttributes(Module)

检索应用于模块的自定义属性的数组。Retrieves an array of the custom attributes applied to a module. 参数指定模块。A parameter specifies the module.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::Module ^ element);
public static Attribute[] GetCustomAttributes (System.Reflection.Module element);
static member GetCustomAttributes : System.Reflection.Module -> Attribute[]
Public Shared Function GetCustomAttributes (element As Module) As Attribute()

参数

element
Module

一个从 Module 类派生的对象,该类描述可移植的可执行文件。An object derived from the Module class that describes a portable executable file.

返回

一个 Attribute 数组,其中包含应用于 element 的自定义属性;如果不存在任何此类自定义属性,则为空数组。An Attribute array that contains the custom attributes applied to element, or an empty array if no such custom attributes exist.

异常

elementnullelement is null.

示例

下面的代码示例演示如何使用 GetCustomAttributes,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttributes, taking a Module as a parameter.

using namespace System;
using namespace System::Reflection;
using namespace System::ComponentModel;

// Assign some attributes to the module.
// Set the module's CLSCompliant attribute to false
// The CLSCompliant attribute is applicable for /target:module.
[module:Description("A sample description")];
[module:CLSCompliant(false)];
namespace CustAttrs2CS
{
   ref class DemoClass
   {
   public:
      static void Main()
      {
         Type^ clsType = DemoClass::typeid;

         // Get the Module type to access its metadata.
         Module^ module = clsType->Module;

         // Iterate through all the attributes for the module.
         System::Collections::IEnumerator^ myEnum1 = Attribute::GetCustomAttributes( module )->GetEnumerator();
         while ( myEnum1->MoveNext() )
         {
            Attribute^ attr = safe_cast<Attribute^>(myEnum1->Current);

            // Check for the Description attribute.
            if ( attr->GetType() == DescriptionAttribute::typeid )
                        Console::WriteLine( "Module {0} has the description \"{1}\".", module->Name, (dynamic_cast<DescriptionAttribute^>(attr))->Description );
            // Check for the CLSCompliant attribute.
            else

            // Check for the CLSCompliant attribute.
            if ( attr->GetType() == CLSCompliantAttribute::typeid )
                        Console::WriteLine( "Module {0} {1} CLSCompliant.", module->Name, (dynamic_cast<CLSCompliantAttribute^>(attr))->IsCompliant ? (String^)"is" : "is not" );
         }
      }
   };
}


/*
 * Output:
 * Module CustAttrs2CS.exe is not CLSCompliant.
 * Module CustAttrs2CS.exe has the description "A sample description".
 */
using System;
using System.Reflection;
using System.ComponentModel;

// Assign some attributes to the module.
[module:Description("A sample description")]

// Set the module's CLSCompliant attribute to false
// The CLSCompliant attribute is applicable for /target:module.
[module:CLSCompliant(false)]

namespace CustAttrs2CS {
    class DemoClass {
        static void Main(string[] args) {
            Type clsType = typeof(DemoClass);
            // Get the Module type to access its metadata.
            Module module = clsType.Module;

            // Iterate through all the attributes for the module.
            foreach(Attribute attr in Attribute.GetCustomAttributes(module)) {
                // Check for the Description attribute.
                if (attr.GetType() == typeof(DescriptionAttribute))
                    Console.WriteLine("Module {0} has the description " +
                        "\"{1}\".", module.Name, 
                        ((DescriptionAttribute)attr).Description);
                // Check for the CLSCompliant attribute.
                else if (attr.GetType() == typeof(CLSCompliantAttribute))
                    Console.WriteLine("Module {0} {1} CLSCompliant.",
                        module.Name,
                        ((CLSCompliantAttribute)attr).IsCompliant ? 
                            "is" : "is not");
            }
        }
    }
}

/*
 * Output:
 * Module CustAttrs2CS.exe is not CLSCompliant.
 * Module CustAttrs2CS.exe has the description "A sample description".
 */
Imports System.Reflection
Imports System.ComponentModel

' Give the Module some attributes.
<Module: Description("A sample description")> 

' Make the CLSCompliant attribute False.
' The CLSCompliant attribute is applicable for /target:module.
<Module: CLSCompliant(False)> 

Module DemoModule

    Sub Main()
        ' Get the Module type to access its metadata.
        Dim modType As Reflection.Module = GetType(DemoModule).Module
        Dim attr As Attribute
        ' Iterate through all the attributes for the module.
        For Each attr In Attribute.GetCustomAttributes(modType)
            ' Check for the Description attribute.
            If TypeOf attr Is DescriptionAttribute Then
                ' Convert the attribute to access its data.
                Dim descAttr As DescriptionAttribute = _
                    CType(attr, DescriptionAttribute)
                Console.WriteLine("Module {0} has the description ""{1}"".", _
                    modType.Name, descAttr.Description)

            ' Check for the CLSCompliant attribute.
            ElseIf TypeOf attr Is CLSCompliantAttribute Then
                ' Convert the attribute to access its data.
                Dim CLSCompAttr As CLSCompliantAttribute = _
                    CType(attr, CLSCompliantAttribute)
                Dim strCompliant As String
                If CLSCompAttr.IsCompliant Then
                    strCompliant = "is"
                Else
                    strCompliant = "is not"
                End If
                Console.WriteLine("Module {0} {1} CLSCompliant.", _
                    modType.Name, strCompliant)
            End If
        Next
    End Sub
End Module

' Output:
' Module CustAttrs2VB.exe has the description "A sample description".
' Module CustAttrs2VB.exe is not CLSCompliant.

GetCustomAttributes(MemberInfo)

检索应用于类型的成员的自定义属性的数组。Retrieves an array of the custom attributes applied to a member of a type. 参数指定成员。A parameter specifies the member.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::MemberInfo ^ element);
public static Attribute[] GetCustomAttributes (System.Reflection.MemberInfo element);
static member GetCustomAttributes : System.Reflection.MemberInfo -> Attribute[]
Public Shared Function GetCustomAttributes (element As MemberInfo) As Attribute()

参数

element
MemberInfo

一个从 MemberInfo 类派生的对象,该类描述类的构造函数、事件、字段、方法或属性成员。An object derived from the MemberInfo class that describes a constructor, event, field, method, or property member of a class.

返回

一个 Attribute 数组,其中包含应用于 element 的自定义属性;如果不存在任何此类自定义属性,则为空数组。An Attribute array that contains the custom attributes applied to element, or an empty array if no such custom attributes exist.

异常

elementnullelement is null.

element 不是构造函数、方法、属性、事件、类型或字段。element is not a constructor, method, property, event, type, or field.

无法加载自定义属性类型。A custom attribute type cannot be loaded.

示例

下面的代码示例演示如何使用 GetCustomAttribute,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttribute, taking a MemberInfo as a parameter.

using namespace System;
using namespace System::Reflection;
using namespace System::Security;
using namespace System::Runtime::InteropServices;

namespace CustAttrs4CS
{
   // Create a class for Win32 imported unmanaged functions.
   public ref class Win32
   {
   public:

      [DllImport("user32.dll", CharSet = CharSet::Unicode)]
      static int MessageBox( int hWnd, String^ text, String^ caption, UInt32 type );
   };

   public ref class AClass
   {
   public:

      // Add some attributes to the Win32CallMethod.

      [Obsolete("This method is obsolete. Use managed MsgBox instead.")]
      void Win32CallMethod()
      {
         Win32::MessageBox( 0, "This is an unmanaged call.", "Be Careful!", 0 );
      }

   };

   ref class DemoClass
   {
   public:
      static void Main()
      {
         // Get the Class type to access its metadata.
         Type^ clsType = AClass::typeid;

         // Get the type information for the Win32CallMethod.
         MethodInfo^ mInfo = clsType->GetMethod( "Win32CallMethod" );
         if ( mInfo != nullptr )
         {
            // Iterate through all the attributes for the method.
            System::Collections::IEnumerator^ myEnum3 = Attribute::GetCustomAttributes( mInfo )->GetEnumerator();
            while ( myEnum3->MoveNext() )
            {
               Attribute^ attr = safe_cast<Attribute^>(myEnum3->Current);

               // Check for the Obsolete attribute.
               if ( attr->GetType() == ObsoleteAttribute::typeid )
               {
                  Console::WriteLine( "Method {0} is obsolete. "
                  "The message is:", mInfo->Name );
                  Console::WriteLine( (dynamic_cast<ObsoleteAttribute^>(attr))->Message );
               }
               // Check for the SuppressUnmanagedCodeSecurity attribute.
               else

               // Check for the SuppressUnmanagedCodeSecurity attribute.
               if ( attr->GetType() == SuppressUnmanagedCodeSecurityAttribute::typeid )
               {
                  Console::WriteLine( "This method calls unmanaged code "
                  "with no security check." );
                  Console::WriteLine( "Please do not use unless absolutely necessary." );
                  AClass^ myCls = gcnew AClass;
                  myCls->Win32CallMethod();
               }
            }
         }
      }
   };
}


/*
 * Output:
 * Method Win32CallMethod is obsolete. The message is:
 * This method is obsolete. Use managed MsgBox instead.
 * This method calls unmanaged code with no security check.
 * Please do not use unless absolutely necessary.
 */
using System;
using System.Reflection;
using System.Security;
using System.Runtime.InteropServices;

namespace CustAttrs4CS
{

    // Define an enumeration of Win32 unmanaged types
    public enum UnmanagedType
    {
        User,
        GDI,
        Kernel,
        Shell,
        Networking,
        Multimedia
    }

    // Define the Unmanaged attribute.
    public class UnmanagedAttribute : Attribute
    {
        // Storage for the UnmanagedType value.
        protected UnmanagedType thisType;

        // Set the unmanaged type in the constructor.
        public UnmanagedAttribute(UnmanagedType type)
        {
            thisType = type;
        }

        // Define a property to get and set the UnmanagedType value.
        public UnmanagedType Win32Type
        {
            get { return thisType; }
            set { thisType = Win32Type; }
        }
    }

    // Create a class for an imported Win32 unmanaged function.
    public class Win32 {
        [DllImport("user32.dll", CharSet = CharSet.Unicode)]
        public static extern int MessageBox(int hWnd, String text,
            String caption, uint type);
    }

    public class AClass {
        // Add some attributes to Win32CallMethod.
        [Obsolete("This method is obsolete. Use managed MsgBox instead.")]
        [Unmanaged(UnmanagedType.User)]
        public void Win32CallMethod()
        {
            Win32.MessageBox(0, "This is an unmanaged call.", "Caution!", 0);
        }
    }

    class DemoClass {
        static void Main(string[] args)
            {
            // Get the AClass type to access its metadata.
            Type clsType = typeof(AClass);
            // Get the type information for Win32CallMethod.
            MethodInfo mInfo = clsType.GetMethod("Win32CallMethod");
            if (mInfo != null)
            {
                // Iterate through all the attributes of the method.
                foreach(Attribute attr in
                    Attribute.GetCustomAttributes(mInfo)) {
                    // Check for the Obsolete attribute.
                    if (attr.GetType() == typeof(ObsoleteAttribute))
                    {
                        Console.WriteLine("Method {0} is obsolete. " +
                            "The message is:",
                            mInfo.Name);
                        Console.WriteLine("  \"{0}\"",
                            ((ObsoleteAttribute)attr).Message);
                    }

                    // Check for the Unmanaged attribute.
                    else if (attr.GetType() == typeof(UnmanagedAttribute))
                    {
                        Console.WriteLine(
                            "This method calls unmanaged code.");
                        Console.WriteLine(
                            String.Format("The Unmanaged attribute type is {0}.",
                                          ((UnmanagedAttribute)attr).Win32Type));
                        AClass myCls = new AClass();
                        myCls.Win32CallMethod();
                    }
                }
            }
        }
    }
}

/*

This code example produces the following results.

First, the compilation yields the warning, "...This method is
obsolete. Use managed MsgBox instead."
Second, execution yields a message box with a title of "Caution!"
and message text of "This is an unmanaged call."
Third, the following text is displayed in the console window:

Method Win32CallMethod is obsolete. The message is:
  "This method is obsolete. Use managed MsgBox instead."
This method calls unmanaged code.
The Unmanaged attribute type is User.

*/

Imports System.Reflection
Imports System.Security
Imports System.Runtime.InteropServices

' Define an enumeration of Win32 unmanaged types
Public Enum UnmanagedType
    User
    GDI
    Kernel
    Shell
    Networking
    Multimedia
End Enum 'UnmanagedType

' Define the Unmanaged attribute.
Public Class UnmanagedAttribute 
             Inherits Attribute

    ' Storage for the UnmanagedType value.
    Protected thisType As UnmanagedType
    
    ' Set the unmanaged type in the constructor.
    Public Sub New(ByVal type As UnmanagedType) 
        thisType = type
    End Sub
    
    ' Define a property to get and set the UnmanagedType value.
    Public Property Win32Type() As UnmanagedType 
        Get
            Return thisType
        End Get
        Set
            thisType = Win32Type
        End Set
    End Property
End Class

' Create a class for an imported Win32 unmanaged function.
Public Class Win32
    <DllImport("user32.dll", CharSet:=CharSet.Unicode)> _
    Public Shared Function MessageBox(ByVal hWnd As Integer, _
                                      ByVal Text As String, _
                                      ByVal caption As String, _
                                      ByVal type As Integer) As Integer
    End Function 'MessageBox
End Class

Public Class AClass
    ' Add some attributes to Win32CallMethod.
    <Obsolete("This method is obsolete. Use managed MsgBox instead."), _
     Unmanaged(UnmanagedType.User)>  _
    Public Sub Win32CallMethod() 
        Win32.MessageBox(0, "This is an unmanaged call.", "Caution!", 0)    
    End Sub
End Class

Class DemoClass
    Shared Sub Main(ByVal args() As String) 
        ' Get the AClass type to access its metadata.
        Dim clsType As Type = GetType(AClass)
        ' Get the type information for Win32CallMethod.
        Dim mInfo As MethodInfo = clsType.GetMethod("Win32CallMethod")
        If Not (mInfo Is Nothing) Then
            ' Iterate through all the attributes of the method.
            Dim attr As Attribute
            For Each attr In  Attribute.GetCustomAttributes(mInfo)
                ' Check for the Obsolete attribute.
                If attr.GetType().Equals(GetType(ObsoleteAttribute)) Then
                    Console.WriteLine("Method {0} is obsolete. The message is:", mInfo.Name)
                    Console.WriteLine("  ""{0}""", CType(attr, ObsoleteAttribute).Message)
                ' Check for the Unmanaged attribute.
                ElseIf attr.GetType().Equals(GetType(UnmanagedAttribute)) Then
                    Console.WriteLine("This method calls unmanaged code.")
                    Console.WriteLine( _
                            String.Format("The Unmanaged attribute type is {0}.", _
                            CType(attr, UnmanagedAttribute).Win32Type))
                    Dim myCls As New AClass()
                    myCls.Win32CallMethod()
                End If
            Next attr
        End If
    End Sub
End Class

'
'This code example produces the following results. 
'
'First, the compilation yields the warning, "...This method is 
'obsolete. Use managed MsgBox instead."
'Second, execution yields a message box with a title of "Caution!" 
'and message text of "This is an unmanaged call." 
'Third, the following text is displayed in the console window:
'
'Method Win32CallMethod is obsolete. The message is:
'  "This method is obsolete. Use managed MsgBox instead."
'This method calls unmanaged code.
'The Unmanaged attribute type is User.
' 

注解

返回值包含 element 的祖先的自定义属性。The return value contains the custom attributes for ancestors of element.

备注

从 .NET Framework 版本2.0 开始,如果属性以新的元数据格式存储,则此方法将返回方法、构造函数和类型的安全特性。Starting with the .NET Framework version 2.0, this method returns security attributes on methods, constructors, and types if the attributes are stored in the new metadata format. 使用版本2.0 或更高版本编译的程序集将使用新的格式。Assemblies compiled with version 2.0 or later use the new format. 使用早期版本的 .NET Framework 编译的动态程序集和程序集使用旧的 XML 格式。Dynamic assemblies and assemblies compiled with earlier versions of the .NET Framework use the old XML format. 请参阅发出声明性安全特性See Emitting Declarative Security Attributes.

GetCustomAttributes(Assembly)

检索一个数组,它由应用于程序集的自定义属性组成。Retrieves an array of the custom attributes applied to an assembly. 参数指定程序集。A parameter specifies the assembly.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::Assembly ^ element);
public static Attribute[] GetCustomAttributes (System.Reflection.Assembly element);
static member GetCustomAttributes : System.Reflection.Assembly -> Attribute[]
Public Shared Function GetCustomAttributes (element As Assembly) As Attribute()

参数

element
Assembly

一个派生自 Assembly 类的对象,用于描述模块的可重用集合。An object derived from the Assembly class that describes a reusable collection of modules.

返回

一个 Attribute 数组,其中包含应用于 element 的自定义属性;如果不存在任何此类自定义属性,则为空数组。An Attribute array that contains the custom attributes applied to element, or an empty array if no such custom attributes exist.

异常

elementnullelement is null.

示例

下面的示例检索在当前程序集中找到的自定义特性。The following example retrieves the custom attributes found in the current assembly.

using namespace System;
using namespace System::Reflection;

[assembly:AssemblyTitle("CustAttrs1CPP")];
[assembly:AssemblyDescription("GetCustomAttributes() Demo")];
[assembly:AssemblyCompany("Microsoft")];

ref class Example
{};

static void main()
{
    Type^ clsType = Example::typeid;

    // Get the Assembly type to access its metadata.
    Assembly^ assy = clsType->Assembly;

    // Iterate through the attributes for the assembly.
    System::Collections::IEnumerator^ myEnum = Attribute::GetCustomAttributes( assy )->GetEnumerator();
    while ( myEnum->MoveNext() )
    {
       Attribute^ attr = safe_cast<Attribute^>(myEnum->Current);

       // Check for the AssemblyTitle attribute.
       if ( attr->GetType() == AssemblyTitleAttribute::typeid )
          Console::WriteLine( "Assembly title is \"{0}\".", (dynamic_cast<AssemblyTitleAttribute^>(attr))->Title );
          // Check for the AssemblyDescription attribute.
       else
          // Check for the AssemblyDescription attribute.
          if ( attr->GetType() == AssemblyDescriptionAttribute::typeid )
             Console::WriteLine( "Assembly description is \"{0}\".", (dynamic_cast<AssemblyDescriptionAttribute^>(attr))->Description );
          // Check for the AssemblyCompany attribute.
          else if ( attr->GetType() == AssemblyCompanyAttribute::typeid )
             Console::WriteLine( "Assembly company is {0}.", (dynamic_cast<AssemblyCompanyAttribute^>(attr))->Company );
    }
}
// The example displays the following output:
//     Assembly description is "GetCustomAttributes() Demo".
//     Assembly company is Microsoft.
//     Assembly title is "CustAttrs1CPP".
using System;
using System.Reflection;

[assembly: AssemblyTitle("CustAttrs1CS")]
[assembly: AssemblyDescription("GetCustomAttributes() Demo")]
[assembly: AssemblyCompany("Microsoft")]

class Example {
    static void Main() {
        // Get the Assembly object to access its metadata.
        Assembly assy = typeof(Example).Assembly;

        // Iterate through the attributes for the assembly.
        foreach(Attribute attr in Attribute.GetCustomAttributes(assy)) {
            // Check for the AssemblyTitle attribute.
            if (attr.GetType() == typeof(AssemblyTitleAttribute))
                Console.WriteLine("Assembly title is \"{0}\".",
                    ((AssemblyTitleAttribute)attr).Title);

            // Check for the AssemblyDescription attribute.
            else if (attr.GetType() == 
                typeof(AssemblyDescriptionAttribute))
                Console.WriteLine("Assembly description is \"{0}\".",
                    ((AssemblyDescriptionAttribute)attr).Description);

            // Check for the AssemblyCompany attribute.
            else if (attr.GetType() == typeof(AssemblyCompanyAttribute))
                Console.WriteLine("Assembly company is {0}.",
                    ((AssemblyCompanyAttribute)attr).Company);
        }
   }
}
// The example displays the following output:
//     Assembly title is "CustAttrs1CS".
//     Assembly description is "GetCustomAttributes() Demo".
//     Assembly company is Microsoft.
Imports System.Reflection

<Assembly: AssemblyTitle("CustAttrs1VB")> 
<Assembly: AssemblyDescription("GetCustomAttributes() Demo")> 
<Assembly: AssemblyCompany("Microsoft")> 

Module Example
    Sub Main()
        ' Get the Assembly type to access its metadata.
        Dim assy As Reflection.Assembly = GetType(Example).Assembly

        ' Iterate through all the attributes for the assembly.
        For Each attr As Attribute In Attribute.GetCustomAttributes(assy)
            ' Check for the AssemblyTitle attribute.
            If TypeOf attr Is AssemblyTitleAttribute Then
                ' Convert the attribute to access its data.
                Dim attrTitle As AssemblyTitleAttribute = _
                    CType(attr, AssemblyTitleAttribute)
                Console.WriteLine("Assembly title is ""{0}"".", _
                    attrTitle.Title)

            ' Check for the AssemblyDescription attribute.
            ElseIf TypeOf attr Is AssemblyDescriptionAttribute Then
                ' Convert the attribute to access its data.
                Dim attrDesc As AssemblyDescriptionAttribute = _
                    CType(attr, AssemblyDescriptionAttribute)
                Console.WriteLine("Assembly description is ""{0}"".", _
                    attrDesc.Description)

            ' Check for the AssemblyCompany attribute.
            ElseIf TypeOf attr Is AssemblyCompanyAttribute Then
                ' Convert the attribute to access its data.
                Dim attrComp As AssemblyCompanyAttribute = _
                    CType(attr, AssemblyCompanyAttribute)
                Console.WriteLine("Assembly company is {0}.", _
                    attrComp.Company)
            End If
        Next
    End Sub
End Module
' The example displays the following output:
'     Assembly company is Microsoft.
'     Assembly description is "GetCustomAttributes() Demo".
'     Assembly title is "CustAttrs1VB".

注解

备注

从 .NET Framework 版本2.0 开始,如果属性以新的元数据格式存储,则此方法返回安全特性。Starting with the .NET Framework version 2.0, this method returns security attributes if the attributes are stored in the new metadata format. 使用版本2.0 或更高版本编译的程序集将使用新的格式。Assemblies compiled with version 2.0 or later use the new format. 使用早期版本的 .NET Framework 编译的动态程序集和程序集使用旧的 XML 格式。Dynamic assemblies and assemblies compiled with earlier versions of the .NET Framework use the old XML format. 请参阅发出声明性安全特性See Emitting Declarative Security Attributes.

GetCustomAttributes(MemberInfo, Type)

检索应用于类型的成员的自定义属性的数组。Retrieves an array of the custom attributes applied to a member of a type. 参数指定成员和要搜索的自定义属性的类型。Parameters specify the member, and the type of the custom attribute to search for.

public:
 static cli::array <Attribute ^> ^ GetCustomAttributes(System::Reflection::MemberInfo ^ element, Type ^ type);
public static Attribute[] GetCustomAttributes (System.Reflection.MemberInfo element, Type type);
static member GetCustomAttributes : System.Reflection.MemberInfo * Type -> Attribute[]

参数

element
MemberInfo

一个从 MemberInfo 类派生的对象,该类描述类的构造函数、事件、字段、方法或属性成员。An object derived from the MemberInfo class that describes a constructor, event, field, method, or property member of a class.

type
Type

要搜索的自定义属性的类型或基类型。The type, or a base type, of the custom attribute to search for.

返回

一个 Attribute 数组,包含应用于 typeelement 类型的自定义属性;如果不存在此类自定义属性,则为空数组。An Attribute array that contains the custom attributes of type type applied to element, or an empty array if no such custom attributes exist.

异常

elementtypenullelement or type is null.

type 不是从 Attribute 派生的。type is not derived from Attribute.

element 不是构造函数、方法、属性、事件、类型或字段。element is not a constructor, method, property, event, type, or field.

无法加载自定义属性类型。A custom attribute type cannot be loaded.

示例

下面的代码示例演示如何使用 GetCustomAttribute,并采用 @no__t 作为参数。The following code example demonstrates the use of GetCustomAttribute, taking a MemberInfo as a parameter.

using namespace System;
using namespace System::Reflection;
using namespace System::Security;
using namespace System::Runtime::InteropServices;

namespace CustAttrs4CS
{
   // Create a class for Win32 imported unmanaged functions.
   public ref class Win32
   {
   public:

      [DllImport("user32.dll", CharSet = CharSet::Unicode)]
      static int MessageBox( int hWnd, String^ text, String^ caption, UInt32 type );
   };

   public ref class AClass
   {
   public:

      // Add some attributes to the Win32CallMethod.

      [Obsolete("This method is obsolete. Use managed MsgBox instead.")]
      void Win32CallMethod()
      {
         Win32::MessageBox( 0, "This is an unmanaged call.", "Be Careful!", 0 );
      }

   };

   ref class DemoClass
   {
   public:
      static void Main()
      {
         // Get the Class type to access its metadata.
         Type^ clsType = AClass::typeid;

         // Get the type information for the Win32CallMethod.
         MethodInfo^ mInfo = clsType->GetMethod( "Win32CallMethod" );
         if ( mInfo != nullptr )
         {
            // Iterate through all the attributes for the method.
            System::Collections::IEnumerator^ myEnum3 = Attribute::GetCustomAttributes( mInfo )->GetEnumerator();
            while ( myEnum3->MoveNext() )
            {
               Attribute^ attr = safe_cast<Attribute^>(myEnum3->Current);

               // Check for the Obsolete attribute.
               if ( attr->GetType() == ObsoleteAttribute::typeid )
               {
                  Console::WriteLine( "Method {0} is obsolete. "
                  "The message is:", mInfo->Name );
                  Console::WriteLine( (dynamic_cast<ObsoleteAttribute^>(attr))->Message );
               }
               // Check for the SuppressUnmanagedCodeSecurity attribute.
               else

               // Check for the SuppressUnmanagedCodeSecurity attribute.
               if ( attr->GetType() == SuppressUnmanagedCodeSecurityAttribute::typeid )
               {
                  Console::WriteLine( "This method calls unmanaged code "
                  "with no security check." );
                  Console::WriteLine( "Please do not use unless absolutely necessary." );
                  AClass^ myCls = gcnew AClass;
                  myCls->Win32CallMethod();
               }
            }
         }
      }
   };
}


/*
 * Output:
 * Method Win32CallMethod is obsolete. The message is:
 * This method is obsolete. Use managed MsgBox instead.
 * This method calls unmanaged code with no security check.
 * Please do not use unless absolutely necessary.
 */
using System;
using System.Reflection;
using System.Security;
using System.Runtime.InteropServices;

namespace CustAttrs4CS
{

    // Define an enumeration of Win32 unmanaged types
    public enum UnmanagedType
    {
        User,
        GDI,
        Kernel,
        Shell,
        Networking,
        Multimedia
    }

    // Define the Unmanaged attribute.
    public class UnmanagedAttribute : Attribute
    {
        // Storage for the UnmanagedType value.
        protected UnmanagedType thisType;

        // Set the unmanaged type in the constructor.
        public UnmanagedAttribute(UnmanagedType type)
        {
            thisType = type;
        }

        // Define a property to get and set the UnmanagedType value.
        public UnmanagedType Win32Type
        {
            get { return thisType; }
            set { thisType = Win32Type; }
        }
    }

    // Create a class for an imported Win32 unmanaged function.
    public class Win32 {
        [DllImport("user32.dll", CharSet = CharSet.Unicode)]
        public static extern int MessageBox(int hWnd, String text,
            String caption, uint type);
    }

    public class AClass {
        // Add some attributes to Win32CallMethod.
        [Obsolete("This method is obsolete. Use managed MsgBox instead.")]
        [Unmanaged(UnmanagedType.User)]
        public void Win32CallMethod()
        {
            Win32.MessageBox(0, "This is an unmanaged call.", "Caution!", 0);
        }
    }

    class DemoClass {
        static void Main(string[] args)
            {
            // Get the AClass type to access its metadata.
            Type clsType = typeof(AClass);
            // Get the type information for Win32CallMethod.
            MethodInfo mInfo = clsType.GetMethod("Win32CallMethod");
            if (mInfo != null)
            {
                // Iterate through all the attributes of the method.
                foreach(Attribute attr in
                    Attribute.GetCustomAttributes(mInfo)) {
                    // Check for the Obsolete attribute.
                    if (attr.GetType() == typeof(ObsoleteAttribute))
                    {
                        Console.WriteLine("Method {0} is obsolete. " +
                            "The message is:",
                            mInfo.Name);
                        Console.WriteLine("  \"{0}\"",
                            ((ObsoleteAttribute)attr).Message);
                    }

                    // Check for the Unmanaged attribute.
                    else if (attr.GetType() == typeof(UnmanagedAttribute))
                    {
                        Console.WriteLine(
                            "This method calls unmanaged code.");
                        Console.WriteLine(
                            String.Format("The Unmanaged attribute type is {0}.",
                                          ((UnmanagedAttribute)attr).Win32Type));
                        AClass myCls = new AClass();
                        myCls.Win32CallMethod();
                    }
                }
            }
        }
    }
}

/*

This code example produces the following results.

First, the compilation yields the warning, "...This method is
obsolete. Use managed MsgBox instead."
Second, execution yields a message box with a title of "Caution!"
and message text of "This is an unmanaged call."
Third, the following text is displayed in the console window:

Method Win32CallMethod is obsolete. The message is:
  "This method is obsolete. Use managed MsgBox instead."
This method calls unmanaged code.
The Unmanaged attribute type is User.

*/

Imports System.Reflection
Imports System.Security
Imports System.Runtime.InteropServices

' Define an enumeration of Win32 unmanaged types
Public Enum UnmanagedType
    User
    GDI
    Kernel
    Shell
    Networking
    Multimedia
End Enum 'UnmanagedType

' Define the Unmanaged attribute.
Public Class UnmanagedAttribute 
             Inherits Attribute

    ' Storage for the UnmanagedType value.
    Protected thisType As UnmanagedType
    
    ' Set the unmanaged type in the constructor.
    Public Sub New(ByVal type As UnmanagedType) 
        thisType = type
    End Sub
    
    ' Define a property to get and set the UnmanagedType value.
    Public Property Win32Type() As UnmanagedType 
        Get
            Return thisType
        End Get
        Set
            thisType = Win32Type
        End Set
    End Property
End Class

' Create a class for an imported Win32 unmanaged function.
Public Class Win32
    <DllImport("user32.dll", CharSet:=CharSet.Unicode)> _
    Public Shared Function MessageBox(ByVal hWnd As Integer, _
                                      ByVal Text As String, _
                                      ByVal caption As String, _
                                      ByVal type As Integer) As Integer
    End Function 'MessageBox
End Class

Public Class AClass
    ' Add some attributes to Win32CallMethod.
    <Obsolete("This method is obsolete. Use managed MsgBox instead."), _
     Unmanaged(UnmanagedType.User)>  _
    Public Sub Win32CallMethod() 
        Win32.MessageBox(0, "This is an unmanaged call.", "Caution!", 0)    
    End Sub
End Class

Class DemoClass
    Shared Sub Main(ByVal args() As String) 
        ' Get the AClass type to access its metadata.
        Dim clsType As Type = GetType(AClass)
        ' Get the type information for Win32CallMethod.
        Dim mInfo As MethodInfo = clsType.GetMethod("Win32CallMethod")
        If Not (mInfo Is Nothing) Then
            ' Iterate through all the attributes of the method.
            Dim attr As Attribute
            For Each attr In  Attribute.GetCustomAttributes(mInfo)
                ' Check for the Obsolete attribute.
                If attr.GetType().Equals(GetType(ObsoleteAttribute)) Then
                    Console.WriteLine("Method {0} is obsolete. The message is:", mInfo.Name)
                    Console.WriteLine("  ""{0}""", CType(attr, ObsoleteAttribute).Message)
                ' Check for the Unmanaged attribute.
                ElseIf attr.GetType().Equals(GetType(UnmanagedAttribute)) Then
                    Console.WriteLine("This method calls unmanaged code.")
                    Console.WriteLine( _
                            String.Format("The Unmanaged attribute type is {0}.", _
                            CType(attr, UnmanagedAttribute).Win32Type))
                    Dim myCls As New AClass()
                    myCls.Win32CallMethod()
                End If
            Next attr
        End If
    End Sub
End Class

'
'This code example produces the following results. 
'
'First, the compilation yields the warning, "...This method is 
'obsolete. Use managed MsgBox instead."
'Second, execution yields a message box with a title of "Caution!" 
'and message text of "This is an unmanaged call." 
'Third, the following text is displayed in the console window:
'
'Method Win32CallMethod is obsolete. The message is:
'  "This method is obsolete. Use managed MsgBox instead."
'This method calls unmanaged code.
'The Unmanaged attribute type is User.
' 

注解

返回值包含 element 的祖先的自定义属性。The return value contains the custom attributes for ancestors of element.

备注

从 .NET Framework 版本2.0 开始,如果属性以新的元数据格式存储,则此方法将返回方法、构造函数和类型的安全特性。Starting with the .NET Framework version 2.0, this method returns security attributes on methods, constructors, and types if the attributes are stored in the new metadata format. 使用版本2.0 或更高版本编译的程序集将使用新的格式。Assemblies compiled with version 2.0 or later use the new format. 使用早期版本的 .NET Framework 编译的动态程序集和程序集使用旧的 XML 格式。Dynamic assemblies and assemblies compiled with earlier versions of the .NET Framework use the old XML format. 请参阅发出声明性安全特性See Emitting Declarative Security Attributes.

适用于