Imports System
Imports System.Reflection
Imports Microsoft.VisualBasic
Public MustInherit Class MyMustInheritClass
End Class 'MyMustInheritClass
Public Class [MyClass]
End Class '[MyClass]
Public Class Type_IsMustInherit
    Public Shared Sub Main()
        Try
            ' Check whether the return type of MyMustInheritClass is MustInherit or not.
            Console.WriteLine(ControlChars.NewLine + "Checking whether the type is MustInherit." + ControlChars.NewLine)

            If GetType([MyMustInheritClass]).IsAbstract = True Then
                Console.WriteLine("MyMustInheritClass is {0}", "a MustInherit class.")
            Else
                Console.WriteLine("MyMustInheritClass is {0}", "not a MustInherit class.")
            End If
            ' Check whether the return type of MyClass is MustInherit or not.
            If GetType([MyClass]).IsAbstract = True Then
                Console.WriteLine("MyClass is {0}", "a MustInherit class.")
            Else
                Console.WriteLine("MyClass is {0}", "not a MustInherit class.")
            End If
        Catch e As Exception
            Console.WriteLine("Exception: {0} " + ControlChars.Cr, e.Message.ToString())
        End Try
    End Sub 'Main
End Class 'Type_IsMustInherit

using System;
using System.Reflection;
public abstract class MyAbstractClass 
{
}
public class MyClass
{
}
public class Type_IsAbstract
{
    public static void Main()
    {
        try
        {
            // Check whether the return type of MyAbstractClass is abstract or not.
            Console.WriteLine("\nChecking whether the type is abstract.\n"); 
            Console.WriteLine("MyAbstractClass is {0}", (typeof(MyAbstractClass).IsAbstract) ? "an abstract class." : "not an abstract class.");
            // Check whether the return type of MyClass is abstract or not.
            Console.WriteLine("MyClass is {0}", (typeof(MyClass).IsAbstract) ? "an abstract class." : "not an abstract class.");
        }
        catch( Exception e )
        {
            Console.WriteLine( "Exception: {0} \n", e.Message ); 
        }
    }
}

using namespace System;
using namespace System::Reflection;

public  ref class AbstractClass abstract
{
};

public ref class NonAbstractClass
{
};

int main()
{
    // Check whether the return type of MyAbstractClass is abstract or not.
    Console::WriteLine("\nChecking whether the type is abstract.\n");
    if ((AbstractClass::typeid->IsAbstract))
    {
        Console::WriteLine("The AbstractClass is an abstract class.");
    }
    else
    {
        Console::WriteLine("The AbstractClass is not an abstract class.");
    }

    // Check whether the return type of MyClass is abstract or not.
    if ((NonAbstractClass::typeid->IsAbstract))
    {
        Console::WriteLine("The NonAbstractClass is an abstract class.");
    }
    else
    {
        Console::WriteLine("The NonAbstractClass is not an abstract class.");
    }
};