C# delegate event关系

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有几篇文章写的蛮好

点击打开链接http://www.tracefact.net/csharp-programming/delegates-and-events-in-csharp.aspx

点击打开链接http://www.cnblogs.com/lin614/archive/2007/01/30/634576.html

起因：

发现这个event加不加的无所谓嘛，都可以执行的，后来发现有玄机的，参看上面2篇文章。

//public EventHandler<CarInfoArgs> noticeDelegate;
public event EventHandler<CarInfoArgs> noticeDelegate;

class Program    {        static void Main(string[] args)        {            Dealer xiaowang = new Dealer("xiaowang");            Consumer lilaoban = new Consumer();            Consumer zhanglaoban = new Consumer();            xiaowang.noticeDelegate +=new EventHandler<CarInfoArgs>(                lilaoban.getNotice);            xiaowang.noticeDelegate += zhanglaoban.getNotice;            xiaowang.notice("qq");            xiaowang.noticeDelegate -= zhanglaoban.getNotice;            xiaowang.notice("handrover");            //xiaowang.noticeDelegate = null;            Console.ReadLine();        }        static void xiaowang_noticeDelegate(object sender, CarInfoArgs e)        {            throw new NotImplementedException();        }    }    class CarInfoArgs :EventArgs{            public string carinfo { get; set; }            public CarInfoArgs(string car)            {                this.carinfo = car;            }        }        class Dealer {             public string name { get; set; }            public Dealer(string name)            {                this.name = name;            }            //public EventHandler<CarInfoArgs> noticeDelegate;            public event EventHandler<CarInfoArgs> noticeDelegate;            public void notice(string car) {                if (noticeDelegate != null)                {                    noticeDelegate(this, new CarInfoArgs(car));                }                            }        }        class Consumer {             public void getNotice(object sender, CarInfoArgs e) {                Console.WriteLine("{0} got notice from {1} on car type : {2}",this.ToString(),((Dealer)sender).name,e.carinfo);            }        }