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Type.IsInstanceOfType Method

Determines whether the specified object is an instance of the current Type.

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

Public Overridable Function IsInstanceOfType ( _
	o As Object _
) As Boolean


Type: System.Object
The object to compare with the current type.

Return Value

Type: System.Boolean
true if the current Type is in the inheritance hierarchy of the object represented by o, or if the current Type is an interface that o supports. false if neither of these conditions is the case, or if o is Nothing, or if the current Type is an open generic type (that is, ContainsGenericParameters returns true).



This method can be overridden by a derived class.


A constructed type is not an instance of its generic type definition. That is, MyGenericList<int> (MyGenericList(Of Integer) in Visual Basic) is not an instance of MyGenericList<T> (MyGenericList(Of T) in Visual Basic).

The following example demonstrates the use of the IsInstanceOfType method.

Imports System
Public Interface IMyIfc
End Interface 'IMyIfc
Public Class [MyClass]
    Implements IMyIfc
End Class '[MyClass]
Public Class MyDerivedClass
    Inherits [MyClass]
End Class 'MyDerivedClass
Class IsInstanceTest
    Public Shared Sub Main()
        Dim imyifcType As Type = GetType(IMyIfc)
        Dim mc As New [MyClass]()
        Dim mcType As Type = mc.GetType()
        Dim mdc = New MyDerivedClass()
        Dim mdcType As Type = mdc.GetType()
        Dim array(10) As Integer
        Dim arrayType As Type = GetType(Array)
        Console.WriteLine("Is int[] an instance of the Array class? {0}.", arrayType.IsInstanceOfType(array))
        Console.WriteLine("Is myclass an instance of MyClass? {0}.", mcType.IsInstanceOfType(mc))
        Console.WriteLine("Is myderivedclass an instance of MyClass? {0}.", mcType.IsInstanceOfType(mdc))
        Console.WriteLine("Is myclass an instance of IMyIfc? {0}.", imyifcType.IsInstanceOfType(mc))
        Console.WriteLine("Is myderivedclass an instance of IMyIfc? {0}.", imyifcType.IsInstanceOfType(mdc))
    End Sub 'Main
End Class 'IsInstanceTest

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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