事件

using System;
class Publisher//出版社
...{
    public delegate void PubComputer(string magazineName);//声明发布电脑杂志事件所需的代理
    public delegate void PubLife(string magazineName);//声明发布生活杂志事件所需的代理
    public event PubComputer OnPubComputer;//事件的声明
    public event PubLife OnPubLife;//事件的声明
    public void issueComputer()//触发事件的方法
    ...{
        if (OnPubComputer != null)
        ...{
            Console.WriteLine("发行<<电脑杂志>>");
            OnPubComputer("电脑杂志");
        }
    }
    public void issueLife()
    ...{
        if (OnPubLife != null)
        ...{
            Console.WriteLine("发行<<生活杂志>>");
            OnPubLife("生活杂志");
        }
    }
}
class Subscriber
...{
    private string name;
    public Subscriber(string name)
    ...{
        this.name = name;
    }
    public void Receive(string magazineName)
    ...{
        Console.WriteLine(name + "已经收到了" + magazineName);
    }
}
class Story
...{
    static void Main()
    ...{
        Publisher Pub = new Publisher();
        Subscriber zs = new Subscriber("张三");
        Pub.OnPubComputer += new Publisher.PubComputer(zs.Receive);
        Subscriber ls = new Subscriber("李四");
        Pub.OnPubComputer += new Publisher.PubComputer(ls.Receive);
        Pub.OnPubLife += new Publisher.PubLife(ls.Receive);
        Pub.issueComputer();
        Pub.issueLife();
        Console.WriteLine();
        Console.WriteLine("一年后");
        Pub.OnPubComputer -= new Publisher.PubComputer(ls.Receive);
        Pub.issueComputer();
        Pub.issueLife();
    }
}