public Observable(QuackObservable duck) { this.duck = duck; }
public void update(QuackObservable duck) { Console.WriteLine("Quackologist: " + duck + " just quacked."); }
public void Update(QuackObservable duck) { Console.WriteLine("观察者:" + duck + " 正在叫"); }
public Observable(QuackObservable duck) { m_duck = duck; }
public ReadheadDuck() { observable = new Observable(this); }
public MallardDuck() { observable = new Observable(this); }