C# delegate event关系

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);
}
}