static void Main(string[] args) { var rubber = new MallardDuck(); rubber.PerformQuack(); rubber.PerformFly(); rubber.setFlyBehavior(new FlyNoWay()); rubber.setQuackBehavior(new QuackNoWay()); rubber.PerformQuack(); rubber.PerformFly(); //var decoyDuck = new DecoyDuck(); //decoyDuck.PerformQuack(); //decoyDuck.PerformFly(); Console.ReadKey(); }