MemberInfo.GetCustomAttributes MemberInfo.GetCustomAttributes MemberInfo.GetCustomAttributes MemberInfo.GetCustomAttributes Method

Definition

When overridden in a derived class, returns custom attributes applied to this member.

Overloads

GetCustomAttributes(Boolean) GetCustomAttributes(Boolean) GetCustomAttributes(Boolean) GetCustomAttributes(Boolean)

When overridden in a derived class, returns an array of all custom attributes applied to this member.

GetCustomAttributes(Type, Boolean) GetCustomAttributes(Type, Boolean) GetCustomAttributes(Type, Boolean) GetCustomAttributes(Type, Boolean)

When overridden in a derived class, returns an array of custom attributes applied to this member and identified by Type.

GetCustomAttributes(Boolean) GetCustomAttributes(Boolean) GetCustomAttributes(Boolean) GetCustomAttributes(Boolean)

When overridden in a derived class, returns an array of all custom attributes applied to this member.

public:
 abstract cli::array <System::Object ^> ^ GetCustomAttributes(bool inherit);
public abstract object[] GetCustomAttributes (bool inherit);
abstract member GetCustomAttributes : bool -> obj[]
Public MustOverride Function GetCustomAttributes (inherit As Boolean) As Object()
Parameters
inherit
Boolean Boolean Boolean Boolean

true to search this member's inheritance chain to find the attributes; otherwise, false. This parameter is ignored for properties and events.

Returns
Object[]

An array that contains all the custom attributes applied to this member, or an array with zero elements if no attributes are defined.

Implements
Exceptions

A custom attribute type could not be loaded.

Examples

The following example defines a custom attribute and associates the attribute with MyClass.MyMethod, retrieves the attribute at run time, and displays the result.

using namespace System;
using namespace System::Reflection;

// Define a custom attribute with one named parameter.

[AttributeUsage(AttributeTargets::All)]
public ref class MyAttribute: public Attribute
{
private:
   String^ myName;

public:
   MyAttribute( String^ name )
   {
      myName = name;
   }

   property String^ Name 
   {
      String^ get()
      {
         return myName;
      }
   }
};

// Define a class that has the custom attribute associated with one of its members.
public ref class MyClass1
{
public:

   [MyAttribute("This is an example attribute.")]
   void MyMethod( int i )
   {
      return;
   }
};

int main()
{
   try
   {
      // Get the type of MyClass1.
      Type^ myType = MyClass1::typeid;

      // Get the members associated with MyClass1.
      array<MemberInfo^>^myMembers = myType->GetMembers();

      // Display the attributes for each of the members of MyClass1.
      for ( int i = 0; i < myMembers->Length; i++ )
      {
         array<Object^>^myAttributes = myMembers[ i ]->GetCustomAttributes( true );
         if ( myAttributes->Length > 0 )
         {
            Console::WriteLine( "\nThe attributes for the member {0} are: \n", myMembers[ i ] );
            for ( int j = 0; j < myAttributes->Length; j++ )
               Console::WriteLine( "The type of the attribute is {0}.", myAttributes[ j ] );
         }
      }
   }
   catch ( Exception^ e ) 
   {
      Console::WriteLine( "An exception occurred: {0}", e->Message );
   }
}
using System;
using System.Reflection;

// Define a custom attribute with one named parameter.
[AttributeUsage(AttributeTargets.All)]
public class MyAttribute : Attribute
{
    private string myName;
    public MyAttribute(string name)
    {
        myName = name;
    }
    public string Name
    {
        get
        {
            return myName;
        }
    }
}

// Define a class that has the custom attribute associated with one of its members.
public class MyClass1
{
    [MyAttribute("This is an example attribute.")]
    public void MyMethod(int i)
    {
        return;
    }
}

public class MemberInfo_GetCustomAttributes
{
    public static void Main()
    {
        try
        {
            // Get the type of MyClass1.
            Type myType = typeof(MyClass1);
            // Get the members associated with MyClass1.
            MemberInfo[] myMembers = myType.GetMembers();

            // Display the attributes for each of the members of MyClass1.
            for(int i = 0; i < myMembers.Length; i++)
            {
                Object[] myAttributes = myMembers[i].GetCustomAttributes(true);
                if(myAttributes.Length > 0)
                {
                    Console.WriteLine("\nThe attributes for the member {0} are: \n", myMembers[i]);
                    for(int j = 0; j < myAttributes.Length; j++)
                        Console.WriteLine("The type of the attribute is {0}.", myAttributes[j]);
                }
            }
        }
        catch(Exception e)
        {
            Console.WriteLine("An exception occurred: {0}", e.Message);
        }
    }
}
Imports System
Imports System.Reflection
Imports Microsoft.VisualBasic

' Define a custom attribute with one named parameter.
<AttributeUsage(AttributeTargets.All)> Public Class MyAttribute
    Inherits Attribute
    Private myName As String

    Public Sub New(ByVal name As String)
        myName = name
    End Sub 'New

    Public ReadOnly Property Name() As String
        Get
            Return myName
        End Get
    End Property
End Class 'MyAttribute

' Define a class that has the custom attribute associated with one of its members.
Public Class MyClass1

    <MyAttribute("This is an example attribute.")> Public Sub MyMethod(ByVal i As Integer)
        Return
    End Sub 'MyMethod
End Class 'MyClass1


Public Class MemberInfo_GetCustomAttributes

    Public Shared Sub Main()
        Try
            ' Get the type of MyClass1.
            Dim myType As Type = GetType(MyClass1)
            ' Get the members associated with MyClass1.
            Dim myMembers As MemberInfo() = myType.GetMembers()

            ' Display the attributes for each of the members of MyClass1.
            Dim i As Integer
            For i = 0 To myMembers.Length - 1
                Dim myAttributes As [Object]() = myMembers(i).GetCustomAttributes(False)
                If myAttributes.Length > 0 Then
                    Console.WriteLine("The attributes for the member {0} are: ", myMembers(i))
                    Dim j As Integer
                    For j = 0 To myAttributes.Length - 1
                        Console.WriteLine("The type of the attribute is: {0}", myAttributes(j))
                    Next j
                End If
            Next i
        Catch e As Exception
            Console.WriteLine("An exception occurred: {0}.", e.Message)
        End Try
    End Sub 'Main
End Class 'MemberInfo_GetCustomAttributes

Remarks

This method ignores the inherit parameter for properties and events. To search the inheritance chain for attributes on properties and events, use the appropriate overloads of the Attribute.GetCustomAttributes method.

Note

In the .NET Framework version 2.0, this method returns security attributes on methods, constructors, and types if they are stored in the new metadata format. Assemblies compiled with version 2.0 use this format. Dynamic assemblies and assemblies compiled with earlier versions of the .NET Framework use the old XML format. See Emitting Declarative Security Attributes.

See Also

GetCustomAttributes(Type, Boolean) GetCustomAttributes(Type, Boolean) GetCustomAttributes(Type, Boolean) GetCustomAttributes(Type, Boolean)

When overridden in a derived class, returns an array of custom attributes applied to this member and identified by Type.

public:
 abstract cli::array <System::Object ^> ^ GetCustomAttributes(Type ^ attributeType, bool inherit);
public abstract object[] GetCustomAttributes (Type attributeType, bool inherit);
abstract member GetCustomAttributes : Type * bool -> obj[]
Public MustOverride Function GetCustomAttributes (attributeType As Type, inherit As Boolean) As Object()
Parameters
attributeType
Type Type Type Type

The type of attribute to search for. Only attributes that are assignable to this type are returned.

inherit
Boolean Boolean Boolean Boolean

true to search this member's inheritance chain to find the attributes; otherwise, false. This parameter is ignored for properties and events.

Returns
Object[]

An array of custom attributes applied to this member, or an array with zero elements if no attributes assignable to attributeType have been applied.

Implements
Exceptions

A custom attribute type cannot be loaded.

Examples

The following example defines a class named BaseClass that has two non-inherited members: a thread static field named total and a non-CLS-compliant method named MethodA. A class named DerivedClass inherits from BaseClass and overrides its MethodA method. Note that no attributes are applied to the members of DerivedClass. The example iterates the members of DerivedClass to determine whether the CLSCompliantAttribute or ThreadStaticAttribute attribute as been applied to them. Because inherit is true, the method searches the inheritance hierarchy of DerivedClass for the specified attribute. As the output from the example shows, the total field is decorated with the ThreadStaticAttribute attribute, and the MethodA method is decorated with the CLSCompliantAttribute attribute.

using System;

public class BaseClass
{
   [ThreadStatic] public int total;
   
   [CLSCompliant(false)] public virtual uint MethodA()
   {
      return (uint) 100;
   }
}

public class DerivedClass : BaseClass
{
   public override uint MethodA()
   {
      total++;
      return 200;
   }
}

public class Example
{
   public static void Main()
   {
      Type t = typeof(DerivedClass);
      Console.WriteLine("Members of {0}:", t.FullName);
      foreach (var m in t.GetMembers())
      {
         bool hasAttribute = false;
         Console.Write("   {0}: ", m.Name);
         if (m.GetCustomAttributes(typeof(CLSCompliantAttribute), true).Length > 0) {
            Console.Write("CLSCompliant");
            hasAttribute = true;
         }
         if (m.GetCustomAttributes(typeof(ThreadStaticAttribute), true).Length > 0) {
            Console.Write("ThreadStatic");
            hasAttribute = true;
         }
         if (! hasAttribute)
            Console.Write("No attributes");

         Console.WriteLine();
      }
   }
}
// The example displays the following output:
//       Members of DerivedClass:
//          MethodA: CLSCompliant
//          ToString: No attributes
//          Equals: No attributes
//          GetHashCode: No attributes
//          typeof: No attributes
//          .ctor: No attributes
//          total: ThreadStatic
Public Class BaseClass
   <ThreadStatic> Public total As Integer
   
   <CLSCompliant(False)> Public Overridable Function MethodA() As UInt32
      Return CUInt(100)
   End Function
End Class

Public Class DerivedClass : Inherits BaseClass
   Public Overrides Function MethodA() As UInt32
      total += 1
      Return 200
   End Function
End Class

Module Example
   Public Sub Main()
      Dim t As Type = GetType(DerivedClass)
      Console.WriteLine("Members of {0}:", t.FullName)
      For Each m In t.GetMembers()
         Dim hasAttribute As Boolean = False
         Console.Write("   {0}: ", m.Name)
         If m.GetCustomAttributes(GetType(CLSCompliantAttribute), True).Length > 0 Then
            Console.Write("CLSCompliant")
            hasAttribute = True
         End If
         If m.GetCustomAttributes(GetType(ThreadStaticAttribute), True).Length > 0 Then
            Console.Write("ThreadStatic")
            hasAttribute = True
         End If
         If Not hasAttribute Then
            Console.Write("No attributes")
         End If
         Console.WriteLine()
      Next
   End Sub
End Module
' The example displays the following output:
'       Members of DerivedClass:
'          MethodA: CLSCompliant
'          ToString: No attributes
'          Equals: No attributes
'          GetHashCode: No attributes
'          GetType: No attributes
'          .ctor: No attributes
'          total: ThreadStatic

Remarks

This method ignores the inherit parameter for properties and events. To search the inheritance chain for attributes on properties and events, use the appropriate overloads of the Attribute.GetCustomAttributes method.

Note

In 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. Assemblies compiled with version 2.0 use this format. Dynamic assemblies and assemblies compiled with earlier versions of the .NET Framework use the old XML format. See Emitting Declarative Security Attributes.

Applies to