C#中自定义事件和委托实例

       //定义delegate
       publicdelegatevoidTestEventHandler(objectsender,TestEventArgse);
       //用event关键字声明事件对象
       publiceventTestEventHandlerTestEvent;

       //事件触发方法
       protectedvirtualvoidOnTestEvent(TestEventArgse)
       {
           if(TestEvent!=null)
               TestEvent(this,e);
       }

       //引发事件
       publicvoidRaiseEvent(charkeyToRaiseEvent)
       {
           TestEventArgse=newTestEventArgs(keyToRaiseEvent);
           OnTestEvent(e);
       }

   }
   //监听事件的类
   publicclassTestEventListener
   {
       //定义处理事件的方法，他与声明事件的delegate具有相同的参数和返回值类型
       publicvoidKeyPressed(objectsender,TestEventSource.TestEventArgse)
       {
           Console.WriteLine("发送者：{0}，所按得健为：{1}",sender,e.KeyToRaiseEvent);
       }

       //订阅事件
       publicvoidSubscribe(TestEventSourceevenSource)
       {
           evenSource.TestEvent+=newTestEventSource.TestEventHandler(KeyPressed);
       }
       //取消订阅事件
       publicvoidUnSubscribe(TestEventSourceevenSource)
       {
           evenSource.TestEvent-=newTestEventSource.TestEventHandler(KeyPressed);
       }
   }

   //测试类
   publicclassTest
   {
       publicstaticvoidMain()
       {
           //创建事件源对象
           TestEventSourcees=newTestEventSource();
           //创建监听对象
           TestEventListenerel=newTestEventListener();
           //订阅事件
           Console.WriteLine("订阅事件\n");
           el.Subscribe(es);
           //引发事件
           Console.WriteLine("输入一个字符，再按enter键");
           strings=Console.ReadLine();
           es.RaiseEvent(s.ToCharArray()[0]);
           //取消订阅事件
           Console.WriteLine("\n取消订阅事件\n");
           el.UnSubscribe(es);

           //引发事件
           Console.WriteLine("输入一个字符，再按enter健");
           s=Console.ReadLine();
           es.RaiseEvent(s.ToCharArray()[0]);

       }
   }

}