private static void Main(string[] args) { Console.WriteLine("Hello World!"); IDemo demo = new Demo(); demo.DemoMethod(); demo.DemoPublicDefaultMethod(); demo.DemoVirtualDefaultMethod(); demo.DemoAbstractDefaultMethod(); Console.WriteLine(demo.Message); IDemo.DemoStaticDefaultMethod(); // Static Method // Call method throug Class Object Demo demo1Obj = new Demo(); // So Here you will get any method throug Object. ((IDemo)demo1Obj).DemoMethod(); //-------------------------------------------- IA demoA = new DemoC(); demoA.Display(); demoA.Display1(); IB demoB = new DemoC(); demoB.Display(); demoB.Display2(); ID dObj = new DemoD(); dObj.Display1(); dObj.Display2(); demoA = dObj; demoA.Display(); demoB = dObj; demoB.Display(); }