10. 程序设计: 猫大叫一声，所有的老鼠都开始逃跑，主人被惊醒。(C#语言) 要求： 1.要有联动性，老鼠和主人的行为是被动的。 2.考虑可扩展性，猫的叫声可能引起其他联动效应。 public interface Observer { void Response(); //观察者的响应，如是老鼠见到猫的反映 }

public interface Subject { void AimAt(Observer obs); //针对哪些观察者，这里指猫的要扑捉的对象---老鼠 }

public class Mouse : Observer {

private string name;

public Mouse(string name, Subject subj) { this.name = name; subj.AimAt(this); }

public void Response() { Console.WriteLine(name + attempt to escape!); }

}

public class Master : Observer {

public Master(Subject subj) { subj.AimAt(this); }

public void Response() { Console.WriteLine(Host waken!); }

}

public class Cat : Subject {

private ArrayList observers;

public Cat() { this.observers = new ArrayList(); }

public void AimAt(Observer obs) { this.observers.Add(obs); }

public void Cry() {

Console.WriteLine(Cat cryed!);

foreach (Observer obs in this.observers) { obs.Response(); }

}

}

class MainClass {

static void Main(string[] args)

{

 Cat cat = new Cat();

Mouse mouse1 = new Mouse(mouse1, cat);

Mouse mouse2 = new Mouse(mouse2, cat);

Master master = new Master(cat);

cat.Cry();

}

}