c#事件委托

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代码是理解的亲娘直接开干

using System;using System.Collections;public delegate void AddEventHandler(object sender, EventArgs e);  //声明一个事件委托类型public class ListWithEvent : ArrayList{    public event AddEventHandler Added;    //声明一个事件    protected virtual void OnChanged(EventArgs e)    {        if (Added != null)            Added(this, e);    }    public override int Add(object value)    {        int i = base.Add(value);        OnChanged(EventArgs.Empty);        return i;    }}class EventMethod{    public void ListChanged(object sender, EventArgs e)    {        Console.WriteLine("This is called when the event fires.");    }}class Program{    public static void Main()    {        ListWithEvent List = new ListWithEvent();        EventMethod test = new EventMethod();        List.Added += new AddEventHandler(test.ListChanged);        List.Add("Item 1");        List.Add("Item 2");        Console.Read();    }}

懂了么？

不管，继续

using System;class Publisher{    public delegate void Publish(); //修饰符  关键字    类型   委托名    public event Publish OnPublish;   //定义Pubish委托类型事件    public void issue()     //定义触发事件的方法    {        if (OnPublish != null)        //事件不为空        {            Console.WriteLine("发行刊物！");            OnPublish();             //事件发生        }    }}class Subscriber{    public void Receive()    {        Console.WriteLine("订阅者已收到刊物！");    }}class Story{    static void Main()    {        Publisher Pub = new Publisher();        Subscriber Sub = new Subscriber();        Pub.OnPublish += new Publisher.Publish(Sub.Receive); //此时往委托的对象->事件里存放一个新的委托对象（即事件）；此时该事件不为空，参数是目标对象的方法        Pub.issue();   //触发事件                                                       Console.Read();    }}

哇哈哈！没事

来吧！

using System;class Publisher    //出版社{    public delegate void PubComputer(string magazineName);    public delegate void PubLife(string magzineName);    public event PubComputer OnPubComputer;    public event PubLife OnPubLife;    public void issueComputer()   //定义触发事件的方法    {        if (OnPubComputer != null)               {            Console.WriteLine("发行《电脑》杂志！");            OnPubComputer("电脑杂志");   //事件发生   利用委托传递参数        }    }    public void issureLife()   //定义触发事件的方法    {        if (OnPubLife != null)        {            Console.WriteLine("发行《生活》杂志！");            OnPubLife("生活杂志");   //事件发生        }    }}class Subscriber      //订阅者{    private string name;    public Subscriber(string name)    {        this.name = name;    }    public void Receive(string magazineName)    {        Console.WriteLine(name + "已经收到" + magazineName);    }}class Story{    static void Main()    {        Publisher Pub = new Publisher();        Subscriber zs = new Subscriber("张三");        Pub.OnPubComputer += new Publisher.PubComputer(zs.Receive); //向事件发行者预定一个事件        Subscriber ls = new Subscriber("李四");        Pub.OnPubComputer += new Publisher.PubComputer(ls.Receive);  //触发事件  引发与之关联的方法        Pub.OnPubLife += new Publisher.PubLife(ls.Receive);//new操作符是创建一个委托的对象                            //此时往委托的对象->事件里存放一个新的委托对象（即事件），与目标对象方法关联；此时该事件不为空  OnPublife！=null
 Pub.issueComputer(); //触发事件 Pub.issureLife(); Console.WriteLine(); Console.WriteLine("一年以后"); Pub.OnPubComputer -= new Publisher.PubComputer(ls.Receive); Pub.issueComputer(); Pub.issureLife(); Console.Read(); }}


现在好点了吧

再来大招！！！
using System;using System.Collections;class PubEventArgs : EventArgs{    private readonly string m_magazineName;    private readonly string m_pubDate;    public PubEventArgs(string magazineName, DateTime PubDate)    {        m_magazineName = magazineName;        //PubDate = new DateTime();        m_pubDate = PubDate.ToString();    }    public string magazineName   //属性    {        get        {            return m_magazineName;        }    }    public string pubDate    //属性    {        get        {            return m_pubDate;        }    }}class Publisher{    public delegate void PubComputerEventHandler(object sender, PubEventArgs e);    public delegate void PubLifeEventHandler(object sender, PubEventArgs e);         public event PubComputerEventHandler PubComputer;             public event PubLifeEventHandler PubLife;                             protected virtual void OnPubComputer(PubEventArgs e)                {                                                                          PubComputerEventHandler handler = PubComputer; //防止可能出现的线程同步问题          if (handler != null)    //当事件绑定对应的方法时，该事件非空                            {                                                                                      handler(this, e);   //this  为触发该事件的类的对象    e 为包含事件参数的类的对象              }                                                                                        }                                                                                        protected virtual void OnPubLife(PubEventArgs e)       {        PubLifeEventHandler handler = PubLife;  //与上同        if (handler != null)        {            handler(this, e);        }    }    public void issueComputer(string magazineName, DateTime pubDate)    {        Console.WriteLine("发行" + magazineName);        OnPubComputer(new PubEventArgs(magazineName, pubDate));    }    public void issueLife(string magazineName, DateTime pubDate)    {        Console.WriteLine("发行" + magazineName);        OnPubLife(new PubEventArgs(magazineName, pubDate));    }}class Subscriber{    private string name;    public Subscriber(string name)    {        this.name = name;    }    public void Receive(object sender, PubEventArgs e)    {        Console.WriteLine(e.pubDate + "" + name + "已经收到" + e.magazineName);    }}class Story{    static void Main()    {        Publisher Pub = new Publisher();        Subscriber zs = new Subscriber("张三");        Pub.PubComputer += new Publisher.PubComputerEventHandler(zs.Receive);        Subscriber ls = new Subscriber("李四");        Pub.PubComputer += new Publisher.PubComputerEventHandler(ls.Receive);        Pub.PubLife += new Publisher.PubLifeEventHandler(ls.Receive);        Pub.issueComputer("电脑杂志", Convert.ToDateTime("2010-9-15"));        Pub.issueLife("生活杂志", Convert.ToDateTime("2010-9-15"));        Console.WriteLine();        Console.WriteLine("一年以后");        Pub.PubComputer -= new Publisher.PubComputerEventHandler(ls.Receive);        Pub.issueComputer("电脑杂志", Convert.ToDateTime("2011-9-15"));        Pub.issueLife("生活杂志", Convert.ToDateTime("2011-9-15"));        Console.Read();    }}



.net Framework 的命名方式  1、事件的命名应使用Pascal Casing 命名方式
   2 声明delegate时，必须使用void类型作为返回值。事件命名方面 例如： eventName事件的事件委托是
EventNameEventHandler,时间接受两个传入参数，一律命名为sender与e。
   3 定义一个提供事件数据的类，对类以EventNameEventArgs 进行命名，从System.EventArgs派生该类，然后添加所有事件特定的成员  
   4 在类中实现时间准则。如果事件不需要传递参数，也要声明两个参数，e
         参数直接使用系统提供的System.EventArgs类。如果传递数据，则要从 System.EventArgs继承一个类，并把数据放在里面。
   5 在引发事件的类中，提供一个受保护的办法。以OnEventName进行命名，在该方法中引发事件。

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