Artículo
11/18/2011

MemberInfo.GetCustomAttributes Method (Boolean)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

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

Namespace: System.Reflection
Assembly: mscorlib (in mscorlib.dll)

Syntax

'Declaration
Public MustOverride Function GetCustomAttributes ( _
    inherit As Boolean _
) As Object()

public abstract Object[] GetCustomAttributes(
    bool inherit
)

Parameters

inherit
Type: System.Boolean
true to search this member's inheritance chain to find the attributes; otherwise, false. This parameter is ignored for properties and events; see Remarks

Return Value

Type: array<System.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

ICustomAttributeProvider.GetCustomAttributes(Boolean)

Exceptions

Exception	Condition
TypeLoadException	A custom attribute type could not be loaded.

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.

Platform Notes

Silverlight for Windows Phone

Some attribute constructor arguments and property values can cause MemberInfo.GetCustomAttributes to fail.

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.

Note:
To run this example, see Building Examples That Use a Demo Method and a TextBlock Control.

Imports System.Reflection

' 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 Example

   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      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
               outputBlock.Text += String.Format("The attributes for the member {0} are: ", myMembers(i)) & vbCrLf
               Dim j As Integer
               For j = 0 To myAttributes.Length - 1
                  outputBlock.Text += String.Format("The type of the attribute is: {0}", myAttributes(j)) & vbCrLf
               Next j
            End If
         Next i
      Catch e As Exception
         outputBlock.Text += String.Format("An exception occurred: {0}.", e.Message) & vbCrLf
      End Try
   End Sub 'Main
End Class 'MemberInfo_GetCustomAttributes

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 Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      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)
            {
               outputBlock.Text += String.Format("\nThe attributes for the member {0} are: \n", myMembers[i]) + "\n";
               for (int j = 0; j < myAttributes.Length; j++)
                  outputBlock.Text += String.Format("The type of the attribute is {0}.", myAttributes[j]) + "\n";
            }
         }
      }
      catch (Exception e)
      {
         outputBlock.Text += String.Format("An exception occurred: {0}", e.Message) + "\n";
      }
   }
}

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

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