个人理解c#的委托和事件，附带例子

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一个很简单的例子：就是同学在寝室睡觉，委托班长，老师上课时给自己发消息！

所以流程就是：

1.注册消息：同学们告诉班长，要给我发消息（这就相当于在班长那里注册了一条委托消息）。

2.检测发送条件：班长检测到老师上课的消息。

3.发送消息：于是就给注册了消息通知的同学发消息。

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace TestDelegate{    public delegate void DianMingDelegate(object sender, string str);    public class Student    {        public string Name;        public Student(string name)        {            Name = name;        }        public void ReciveMsg(object sender, string str)        {            Monster ms = sender as Monster;            Console.WriteLine(Name + " -- 收到" + ms.Name + "的消息：-->" + str);        }    }    public class Monster : Student    {        //public event DianMingDelegate Dmd;        private event DianMingDelegate _dmEvent;        private string _info;        public Monster(string name):base(name)        {        }        // 想要注册点名通知的人来我这里哦        public void Regist(DianMingDelegate d)        {            _dmEvent += d;        }        // 通知注册了的同学        private void Notify()        {            if(_dmEvent != null)            {                _dmEvent(this, _info);            }        }        public void CheckDm(LaoShi ls)        {            _info = "    " + ls.Name + ls.SpeakInfo;            Notify();        }    }    public class LaoShi : Student    {        public bool IsDm;        public string SpeakInfo;        public LaoShi(string name) : base(name)        {                    }        // 点名        public void Dm()        {            IsDm = true;            SpeakInfo = "说：今天要点名！";            Console.WriteLine(SpeakInfo);        }        public void Sk()        {            IsDm = false;            SpeakInfo = "说：今天就不点名了，直接上课！";            Console.WriteLine(Name + SpeakInfo);        }    }    public class TestEvent    {        public static void Main(string[] args)        {            Student s1 = new Student("小明");            Student s2 = new Student("小红");            Monster m1 = new Monster("班长");            // 这里点名事件设为public            // 向班长注册点名通知事件            //m1.Dmd += s1.ReciveBzMsg;            //m1.Dmd += s2.ReciveBzMsg;            //m1.Dmd += m1.ReciveBzMsg;            // 这里点名事件设为private            m1.Regist(s1.ReciveMsg);            m1.Regist(s2.ReciveMsg);            m1.Regist(m1.ReciveMsg);            LaoShi ls = new LaoShi("化学老师");            //ls.Dm();            ls.Sk();            m1.CheckDm(ls);            Console.ReadKey();        }            }}

如果有问题，请指出，谢谢！

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