This documentation is archived and is not being maintained.

Type.GetDefaultMembers Method

Searches for the members defined for the current Type whose DefaultMemberAttribute is set.

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

Public Overridable Function GetDefaultMembers As MemberInfo()
Dim instance As Type
Dim returnValue As MemberInfo()

returnValue = instance.GetDefaultMembers
public MemberInfo[] GetDefaultMembers ()
public function GetDefaultMembers () : MemberInfo[]

Return Value

An array of MemberInfo objects representing all default members of the current Type. -or- An empty array of type MemberInfo, if the current Type does not have default members.

This method can be overridden by a derived class.

Members include properties, methods, fields, events, and so on.

The following table shows what members of a base class are returned by the Get methods when reflecting on a type.

Member Type








Yes. A field is always hide-by-name-and-signature.


Not applicable

The common type system rule is that the inheritance is the same as that of the methods that implement the property. Reflection treats properties as hide-by-name-and-signature. See note 2 below.



Yes. A method (both virtual and non-virtual) can be hide-by-name or hide-by-name-and-signature.

Nested Type




Not applicable

The common type system rule is that the inheritance is the same as that of the methods that implement the property. Reflection treats properties as hide-by-name-and-signature. See note 2 below.

  1. Hide-by-name-and-signature considers all of the parts of the signature, including custom modifiers, return types, parameter types, sentinels, and unmanaged calling conventions. This is a binary comparison.

  2. For reflection, properties and events are hide-by-name-and-signature. If you have a property with both a get and a set accessor in the base class, but the derived class has only a get accessor, the derived class property hides the base class property, and you will not be able to access the setter on the base class.

  3. Custom attributes are not part of the common type system.

If the current Type represents a constructed generic type, this method returns the MemberInfo objects with the type parameters replaced by the appropriate type arguments. For example, if class C<T> has a property P that returns T, calling GetDefaultMembers on C<int> returns int P in C# (Property P As Integer in Visual Basic).

If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the members of the class constraint, or the members of Object if there is no class constraint.

The following example obtains the default member information of MyClass and displays the default members.

Imports System
Imports System.Reflection
Imports System.IO
Imports Microsoft.VisualBasic

<DefaultMemberAttribute("Age")> Public Class [MyClass]

    Public Sub Name(ByVal s As String)
    End Sub 'Name

    Public ReadOnly Property Age() As Integer
            Return 20
        End Get
    End Property

    Public Shared Sub Main()
            Dim myType As Type = GetType([MyClass])
            Dim memberInfoArray As MemberInfo() = myType.GetDefaultMembers()
            If memberInfoArray.Length > 0 Then
                Dim memberInfoObj As MemberInfo
                For Each memberInfoObj In memberInfoArray
                    Console.WriteLine("The default member name is: " + memberInfoObj.ToString())
                Next memberInfoObj
                Console.WriteLine("No default members are available.")
            End If
        Catch e As InvalidOperationException
            Console.WriteLine("InvalidOperationException: " + e.Message)
        Catch e As IOException
            Console.WriteLine("IOException: " + e.Message)
        Catch e As Exception
            Console.WriteLine("Exception: " + e.Message)
        End Try
    End Sub 'Main
End Class '[MyClass]

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

/** @attribute DefaultMemberAttribute("Age")
public class MyClass
    public void Name(String s)
    } //Name

    /** @property 
    public int get_Age()
        return 20;
    } //get_Age

    public static void main(String[] args)
        try {
            Type myType = MyClass.class.ToType();
            MemberInfo memberInfoArray[] = myType.GetDefaultMembers();
            if (memberInfoArray.length > 0) {
                for (int iCtr = 0; iCtr < memberInfoArray.length; iCtr++) {
                    MemberInfo memberInfoObj = memberInfoArray[iCtr];
                    Console.WriteLine("The default member name is: "
                        + memberInfoObj.ToString());
            else {
                Console.WriteLine("No default members are available.");
        catch (InvalidOperationException e) {
            Console.WriteLine("InvalidOperationException: " + e.get_Message());
        catch (IOException e) {
            Console.WriteLine("IOException: " + e.get_Message());
        catch (System.Exception e) {
            Console.WriteLine("Exception: " + e.get_Message());
    } //main
} //MyClass

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