[2005] invoking method

hopefully someone can help me out here. i'm trying to use reflection to invoke the dispose method within a class but it keeps throwing an exception
here's my code

vb Code:

If m_DataSource.GetType.GetInterface("IDisposable") IsNot Nothing Then
                Dim obj As Type = m_DataSource.GetType.GetInterface("IDisposable")
                If obj IsNot Nothing Then
                    obj.InvokeMember("Dispose", Reflection.BindingFlags.DeclaredOnly Or Reflection.BindingFlags.Public Or Reflection.BindingFlags.NonPublic Or Reflection.BindingFlags.Instance Or Reflection.BindingFlags.InvokeMethod, Nothing, Nothing, Nothing)
 
                End If
            End If

It appears that you are just trying to invoke the method on a type and not on an instance of that type. What is the exception you are getting?