<ComVisibleAttribute(True)> _
Public Overridable Function IsSubclassOf ( _
    c As Type _
) As Boolean

Dim instance As Type
Dim c As Type
Dim returnValue As Boolean

returnValue = instance.IsSubclassOf(c)

[ComVisibleAttribute(true)]
public virtual bool IsSubclassOf(
    Type c
)

[ComVisibleAttribute(true)]
public:
virtual bool IsSubclassOf(
    Type^ c
)

public function IsSubclassOf(
    c : Type
) : boolean

Implements

The IsSubclassOf method cannot be used to determine whether an interface derives from another interface, or whether a class implements an interface. Use the GetInterface method for that purpose. Note that if a type is dervived from an interface, this method returns true for that type being a subclass of Object.

If the current Type represents a type parameter in the definition of a generic type or generic method, it derives from its class constraint or from System..::.Object if it has no class constraint.

Note:
If the IsSubclassOf is the converse of IsAssignableFrom. That is, if t1.IsSubclassOf(t2) is true, then t2.IsAssignableFrom(t1) is also true.

This method can be overridden by a derived class.

The following example demonstrates the use of the IsSubclassOf method by creating an instance of a class and an instance of its derived class.

Imports System

Public Class Class1
End Class

Public Class DerivedC1
    Inherits Class1
End Class

Class IsSubclassTest

    Public Shared Sub Main()
        Dim myC1 As Class1 = New Class1
        Dim myDClass As DerivedC1 = New DerivedC1
        Dim myClassType As Type = myC1.GetType
        Dim myDClassType As Type = myDClass.GetType

        ' Returns true:
        Console.WriteLine("myDClass subclass of myClass: {0}", myDClassType.IsSubclassOf(myClassType))
        Console.ReadLine()
    End Sub
End Class

using System;

public class Class1 { }
public class DerivedC1 : Class1 { }

class IsSubclassTest
{
    public static void Main()
    {
        Class1 myClass = new Class1();
        DerivedC1 myDClass = new DerivedC1();
        Type myClassType = myClass.GetType();
        Type myDClassType = myDClass.GetType();

        // Returns true:
        Console.WriteLine("myDClass subclass of myClass: {0}", myDClassType.IsSubclassOf(myClassType));
        Console.ReadLine();
    }
}

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

.NET Framework

.NET Compact Framework

XNA Framework

Reference