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MemberInfo.IsDefined Method

When overridden in a derived class, indicates whether one or more instance of attributeType is applied to this member.

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

'Declaration
Public MustOverride Function IsDefined ( _
	attributeType As Type, _
	inherit As Boolean _
) As Boolean
'Usage
Dim instance As MemberInfo
Dim attributeType As Type
Dim inherit As Boolean
Dim returnValue As Boolean

returnValue = instance.IsDefined(attributeType, inherit)
public abstract boolean IsDefined (
	Type attributeType, 
	boolean inherit
)
public abstract function IsDefined (
	attributeType : Type, 
	inherit : boolean
) : boolean

Parameters

attributeType

The Type object to which the custom attributes are applied.

inherit

Specifies whether to search this member's inheritance chain to find the attributes.

Return Value

true if one or more instance of attributeType is applied to this member; otherwise false.

The following example determines whether the specified attribute is applied to the specified member.

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_IsDefined

    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
                ' Display the attribute if it is of type MyAttribute.
                If myMembers(i).IsDefined(GetType(MyAttribute), False) Then
                    Dim myAttributes As [Object]() = myMembers(i).GetCustomAttributes(GetType(MyAttribute), False)
                    Console.WriteLine(ControlChars.Cr + "The attributes of type MyAttribute for the member {0} are: " + ControlChars.Cr, myMembers(i))
                    Dim j As Integer
                    For j = 0 To myAttributes.Length - 1
                        ' Display the value associated with the attribute.
                        Console.WriteLine("The value of the attribute is : ""{0}""", CType(myAttributes(j), MyAttribute).Name)
                    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_IsDefined

import System.*;
import System.Reflection.*;

// Define a custom attribute with one named parameter.
/** @attribute AttributeUsage(AttributeTargets.All)
 */
public class MyAttribute extends Attribute
{
    private String myName;

    public MyAttribute(String name)
    {
        myName = name;
    } //MyAttribute

    /** @property 
     */
    public String get_Name()
    {
        return myName;
    } //get_Name
} //MyAttribute

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

public class MemberInfo_GetCustomAttributes_IsDefined
{
    public static void main(String[] args)
    {
        try {
            // Get the type of MyClass1.
            Type myType = MyClass1.class.ToType();

            // 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++) {
                // Display the attribute if it is of type MyAttribute.
                if (((MemberInfo)myMembers.get_Item(i)).
                    IsDefined(MyAttribute.class.ToType(), false)) {
                    Object myAttributes[] = ((MemberInfo)myMembers.get_Item(i)).
                        GetCustomAttributes(MyAttribute.class.ToType(), false);
                    Console.WriteLine("\nThe attributes of type MyAttribute for"
                        + " the member {0} are: \n", myMembers.get_Item(i));

                    for (int j = 0; j < myAttributes.length; j++) {
                        // Display the value associated with the attribute.
                        Console.WriteLine("The value of the attribute is : \"" 
                            + "{0}\"", ((MyAttribute)myAttributes.get_Item(j)).
                            get_Name());
                    }
                }
            }
        }
        catch (System.Exception e) {
            Console.WriteLine("An exception occurred: {0}", e.get_Message());
        }
    } //main
} //MemberInfo_GetCustomAttributes_IsDefined

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.

.NET Framework

Supported in: 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0
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