Event 与 Delegate的区别,还是有区别的

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1. event就是delegate的一种应用,加上event的delegate能做的事情,与单纯delegate都能做到。

2. 加了event的delegate变量就当是它给外面的世界只显示了两个东西:+=、-=。   
 外面的世界既不能对他赋值(=操作),也不能调用它(myDelegate())。  

举个实例如下:

publikc class Test

{

   public delegate void MyEventHandler(object sender, EventArg e);

   public event MyEventHandler myEvent;

   public MyEventHandler myDelegate;

   public void F1(object sender, EventArg e){}

   public void F2(object sender, EventArg e){}

}

public class App1

{

   void Main()

   {

       Test t1 = new Test();

       t1.myEvent += new  MyEventHandler(t1.F1); //Correct

       t1.myDelegate +=new MyEventHandler(t1.F1); //Correct

       t1.myEvent(); //Wrong

       t1.myDelegate(); //Correct

       t1.myEvent = new MyEventHandler(t1.F1); //Wrong

       t1.myDelegate = new MyEventHandler(t1.F1); //Correct

   }

}

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