C#中自定义事件和委托实例

                KeyToRaiseEvent = keyToRaiseEvent;
            }
        }

 

        //定义delegate
        public delegate void TestEventHandler(object sender, TestEventArgs e);
        //用event 关键字声明事件对象
        public event TestEventHandler TestEvent;

        //事件触发方法
        protected virtual void OnTestEvent(TestEventArgs e)
        {
            if (TestEvent != null)
                TestEvent(this, e);
        }

        //引发事件
        public void RaiseEvent(char keyToRaiseEvent)
        {
            TestEventArgs e = new TestEventArgs(keyToRaiseEvent);
            OnTestEvent(e);
        }

    }
    //监听事件的类
    public class TestEventListener
    {
        //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
        public void KeyPressed(object sender, TestEventSource.TestEventArgs e)
        {
            Console.WriteLine("发送者：{0}，所按得健为：{1}", sender, e.KeyToRaiseEvent);
        }

        //订阅事件
        public void Subscribe(TestEventSource evenSource)
        {
            evenSource.TestEvent += new TestEventSource.TestEventHandler(KeyPressed);
        }
        //取消订阅事件