PropertyAttributes 枚举

定义

定义可能与属性 (Property) 关联的属性 (Attribute)。Defines the attributes that can be associated with a property. 这些特性值定义在 corhdr.h 中。These attribute values are defined in corhdr.h.

此枚举有一个 FlagsAttribute 属性,允许按位组合成员值。

public enum class PropertyAttributes
[System.Flags]
[System.Runtime.InteropServices.ComVisible(true)]
[System.Serializable]
public enum PropertyAttributes
type PropertyAttributes = 
Public Enum PropertyAttributes
继承
PropertyAttributes
属性

字段

HasDefault 4096

指定属性具有默认值。Specifies that the property has a default value.

None 0

指定没有与属性关联的特性。Specifies that no attributes are associated with a property.

Reserved2 8192

保留。Reserved.

Reserved3 16384

保留。Reserved.

Reserved4 32768

保留。Reserved.

ReservedMask 62464

指定一个仅供运行时使用的保留标志。Specifies a flag reserved for runtime use only.

RTSpecialName 1024

指定由元数据内部 API 检查名称编码。Specifies that the metadata internal APIs check the name encoding.

SpecialName 512

指定属性是特殊的,并用名称描述属性的特殊性。Specifies that the property is special, with the name describing how the property is special.

示例

下面的示例生成三个属性并显示PropertyAttributes枚举值。The following example builds three properties and displays the PropertyAttributes enumerated value. 请注意, 只读属性没有 setter, 因此无法更改Caption = statementNote that the read-only property has no setter and thus cannot be changed by.Caption = statement.

using namespace System;
using namespace System::Reflection;

// Define three properties: one read-write, one default,
// and one read only. 
// Define a read-write property.
public ref class Aproperty
{
private:
   String^ caption;

public:
   Aproperty()
      : caption( "A Default caption" )
   {}


   property String^ Caption 
   {
      String^ get()
      {
         return caption;
      }

      void set( String^ value )
      {
         if ( caption != value )
         {
            caption = value;
         }
      }

   }

};


// Define a default property.
public ref class Bproperty
{
private:
   String^ caption;

public:
   Bproperty()
      : caption( "B Default caption" )
   {}

public:
   property String^ Item
   {
      String^ get()
      {
         return "1";
      }

   }

   property String^ Caption 
   {
      String^ get()
      {
         return caption;
      }

      void set( String^ value )
      {
         if ( caption != value )
         {
            caption = value;
         }
      }

   }

};


// Define a read-only property.
public ref class Cproperty
{
private:
   String^ caption;

public:
   Cproperty()
      : caption( "C Default caption" )
   {}


   property String^ Caption 
   {
      String^ get()
      {
         return caption;
      }

   }

};

int main()
{
   Console::WriteLine( "\nReflection.PropertyAttributes" );
   
   // Determine whether a property exists, and change its value.
   Aproperty^ Mypropertya = gcnew Aproperty;
   Bproperty^ Mypropertyb = gcnew Bproperty;
   Cproperty^ Mypropertyc = gcnew Cproperty;
   Console::Write( "\n1. Mypropertya->Caption = {0}", Mypropertya->Caption );
   Console::Write( "\n1. Mypropertyb->Caption = {0}", Mypropertyb->Caption );
   Console::Write( "\n1. Mypropertyc->Caption = {0}", Mypropertyc->Caption );
   
   // Only Mypropertya can be changed, as Mypropertyb is read-only.
   Mypropertya->Caption = "A- This is changed.";
   Mypropertyb->Caption = "B- This is changed.";
   
   // Note that Mypropertyc is not changed because it is read only
   Console::Write( "\n\n2. Mypropertya->Caption = {0}", Mypropertya->Caption );
   Console::Write( "\n2. Mypropertyb->Caption = {0}", Mypropertyb->Caption );
   Console::Write( "\n2. Mypropertyc->Caption = {0}", Mypropertyc->Caption );
   
   // Get the PropertyAttributes enumeration of the property.
   // Get the type.
   Type^ MyTypea = Type::GetType( "Aproperty" );
   Type^ MyTypeb = Type::GetType( "Bproperty" );
   Type^ MyTypec = Type::GetType( "Cproperty" );

   // Get the property attributes.
   PropertyInfo^ Mypropertyinfoa = MyTypea->GetProperty( "Caption" );
   PropertyAttributes Myattributesa = Mypropertyinfoa->Attributes;
   PropertyInfo^ Mypropertyinfob = MyTypeb->GetProperty( "Item" );
   PropertyAttributes Myattributesb = Mypropertyinfob->Attributes;
   PropertyInfo^ Mypropertyinfoc = MyTypec->GetProperty( "Caption" );
   PropertyAttributes Myattributesc = Mypropertyinfoc->Attributes;

   // Display the property attributes value.
   Console::Write( "\n\na- {0}", Myattributesa );
   Console::Write( "\nb- {0}", Myattributesb );
   Console::Write( "\nc- {0}", Myattributesc );
   return 0;
}

// This example displays the following output to the console
//
// Reflection.PropertyAttributes
//
// 1. Mypropertya.Caption = A Default caption
// 1. Mypropertyb.Caption = B Default caption
// 1. Mypropertyc.Caption = C Default caption
//
// 2. Mypropertya.Caption = A- This is changed.
// 2. Mypropertyb.Caption = B- This is changed.
// 2. Mypropertyc.Caption = C Default caption
//
// a- None
// b- None
// c- None
using System;
using System.Reflection;
 
 // Define three properties: one read-write, one default,
 // and one read only. 
public class Aproperty  
    // Define a read-write property.
{
    private string caption = "A Default caption";
    public string Caption
    {
        get{return caption;}
        set
        {
            if (caption != value){caption = value;}
        }
    }
}
public class Bproperty  
    // Define a default property.
{
    private string caption  = "B Default caption";
    public string this [int index]
    {
        get {return "1";}
    }
    public string Caption
    {
  
        get{return caption;}
        set
        {
            if (caption != value){caption = value;}
        }
    }
}
public class Cproperty  
    // Define a read-only property.
{
    private string caption = "C Default caption";
    public string Caption
    {
        get{return caption;}
        // No setting is allowed, because this is a read-only property.
    }
}
  
class propertyattributesenum
{
    public static int Main(string[] args)
    {
        Console.WriteLine("\nReflection.PropertyAttributes");
  
        // Determine whether a property exists, and change its value.
        Aproperty Mypropertya = new Aproperty();
        Bproperty Mypropertyb = new Bproperty();
        Cproperty Mypropertyc = new Cproperty();
  
      
        Console.Write("\n1. Mypropertya.Caption = " + Mypropertya.Caption );
      
        Console.Write("\n1. Mypropertyb.Caption = " + Mypropertyb.Caption );
      
        Console.Write("\n1. Mypropertyc.Caption = " + Mypropertyc.Caption );
  
        // Only Mypropertya can be changed, as Mypropertyb is read-only.
        Mypropertya.Caption = "A- This is changed.";
        Mypropertyb.Caption = "B- This is changed.";
        // Note that Mypropertyc is not changed because it is read only
  
        Console.Write("\n\n2. Mypropertya.Caption = " + Mypropertya.Caption );
  
        Console.Write("\n2. Mypropertyb.Caption = " + Mypropertyb.Caption );
 
        Console.Write("\n2. Mypropertyc.Caption = " + Mypropertyc.Caption );
  
        // Get the PropertyAttributes enumeration of the property.
        // Get the type.
        Type MyTypea = Type.GetType("Aproperty");
        Type MyTypeb = Type.GetType("Bproperty");
        Type MyTypec = Type.GetType("Cproperty");
  
        // Get the property attributes.
        PropertyInfo Mypropertyinfoa = MyTypea.GetProperty("Caption");
        PropertyAttributes Myattributesa = Mypropertyinfoa.Attributes;
        PropertyInfo Mypropertyinfob = MyTypeb.GetProperty("Item");
        PropertyAttributes Myattributesb = Mypropertyinfob.Attributes;
        PropertyInfo Mypropertyinfoc = MyTypec.GetProperty("Caption");
        PropertyAttributes Myattributesc = Mypropertyinfoc.Attributes;
  
        // Display the property attributes value.
      
        Console.Write("\n\na- " + Myattributesa.ToString());

        Console.Write("\nb- " + Myattributesb.ToString());

        Console.Write("\nc- " + Myattributesc.ToString());
        return 0;
    }
}

// This example displays the following output to the console
//
// Reflection.PropertyAttributes
//
// 1. Mypropertya.Caption = A Default caption
// 1. Mypropertyb.Caption = B Default caption
// 1. Mypropertyc.Caption = C Default caption
//
// 2. Mypropertya.Caption = A- This is changed.
// 2. Mypropertyb.Caption = B- This is changed.
// 2. Mypropertyc.Caption = C Default caption
//
// a- None
// b- None
// c- None
Imports System.Reflection

' Make three properties, one read-write, one default,
' and one read-only. 
Public Class Aproperty
    ' Define a read-write property.
    Private myCaption As String = "A Default caption"

    Public Property Caption() As String
        Get
            Return myCaption
        End Get
        Set(ByVal Value As String)
            If myCaption <> value Then
                myCaption = value
            End If
        End Set
    End Property
End Class

Public Class Bproperty
    ' Define a default property.
    Private myCaption As String = "B Default caption"

    Default Public ReadOnly Property Item(ByVal index As Integer) As String
        Get
            Return "1"
        End Get
    End Property

    Public Property Caption() As String

        Get
            Return myCaption
        End Get
        Set(ByVal Value As String)
            If myCaption <> value Then
                myCaption = value
            End If
        End Set
    End Property
End Class

Public Class Cproperty
    ' Define a read-only property.
    Private myCaption As String = "C Default caption"

    Public ReadOnly Property Caption() As String
        Get
            Return myCaption
        End Get
        'No setting is allowed because this property is read-only.
    End Property
End Class


Class propertyattributesenum

    Public Shared Function Main() As Integer
        Console.WriteLine(ControlChars.CrLf & "Reflection.PropertyAttributes")

        ' Determine whether a property exists, and change its value.
        Dim Mypropertya As New Aproperty()
        Dim Mypropertyb As New Bproperty()
        Dim Mypropertyc As New Cproperty()

        Console.Write(ControlChars.CrLf & "1. Mypropertya.Caption = " & _
           Mypropertya.Caption)

        Console.Write(ControlChars.CrLf & "1. Mypropertyb.Caption = " & _
           Mypropertyb.Caption)

        Console.Write(ControlChars.CrLf & "1. Mypropertyc.Caption = " & _
           Mypropertyc.Caption)

        ' Only Mypropertya can be changed because Mypropertyb is read-only.
        Mypropertya.Caption = "A- This is changed."
        Mypropertyb.Caption = "B- This is changed."
        ' Note that Mypropertyc is not changed, because it is read-only.
        Console.Write(ControlChars.CrLf & ControlChars.CrLf & _
           "2. Mypropertya.Caption = " & Mypropertya.Caption)

        Console.Write(ControlChars.CrLf & "2. Mypropertyb.Caption = " & _
           Mypropertyb.Caption)

        Console.Write(ControlChars.CrLf + "2. Mypropertyc.Caption = " & _
           Mypropertyc.Caption)

        ' Get the PropertyAttributes Enumeration of the property.
        ' Get the type.
        Dim MyTypea As Type = Type.GetType("Aproperty")
        Dim MyTypeb As Type = Type.GetType("Bproperty")
        Dim MyTypec As Type = Type.GetType("Cproperty")

        ' Get the property attributes.
        Dim Mypropertyinfoa As PropertyInfo = MyTypea.GetProperty("Caption")
        Dim Myattributesa As PropertyAttributes = Mypropertyinfoa.Attributes
        Dim Mypropertyinfob As PropertyInfo = MyTypeb.GetProperty("Item")
        Dim Myattributesb As PropertyAttributes = Mypropertyinfob.Attributes
        Dim Mypropertyinfoc As PropertyInfo = MyTypec.GetProperty("Caption")
        Dim Myattributesc As PropertyAttributes = Mypropertyinfoc.Attributes

        ' Display the property attributes value.
        Console.Write(ControlChars.CrLf & ControlChars.CrLf & "a- " & _
           Myattributesa.ToString())

        Console.Write(ControlChars.CrLf & "b- " & Myattributesb.ToString())

        Console.Write(ControlChars.CrLf & "c- " & Myattributesc.ToString())
        Return 0
    End Function'    End Function
End Class

' This example displays the following output to the console
'
' Reflection.PropertyAttributes
'
' 1. Mypropertya.Caption = A Default caption
' 1. Mypropertyb.Caption = B Default caption
' 1. Mypropertyc.Caption = C Default caption
'
' 2. Mypropertya.Caption = A- This is changed.
' 2. Mypropertyb.Caption = B- This is changed.
' 2. Mypropertyc.Caption = C Default caption
'
' a- None
' b- None
' c- None

注解

若要获取PropertyAttributes, 请首先获取类TypeTo get the PropertyAttributes, first get the class Type. Type从中PropertyInfo获取。From the Type, get the PropertyInfo. PropertyInfo从中Attributes获取。From the PropertyInfo, get the Attributes.

枚举值是一个数字, 表示对方法实现的属性的按位 "或"。The enumerated value is a number representing the bitwise OR of the attributes implemented on the method.

适用于