public static void Main(string[] args)
        {
            // Create ConcreteComponent and two Decorators
            ConcreteComponentD c  = new ConcreteComponentD();
            ConcreteDecoratorA dA = new ConcreteDecoratorA();
            ConcreteDecoratorB dB = new ConcreteDecoratorB();

            // Link decorators
            dA.SetComponentD(c);
            dB.SetComponentD(dA);

            dB.Operation();

            Console.ReadKey();
        }