Biegral Blog

自己学习过程中的一点笔记：

using System;
using System.Collections.Generic;
using System.Text;

namespace TestApp
{
    class Program
    {
        public static void Main(string[] args)
        {
            Test tst = new Test();
            tst.InitAddEvent(AddEvent); // 传递事件处理函数地址
            tst.CallAddEvent();         // 触发事件

            Console.Read(); // 暂停程序
        }

        // 加法事件
        public static int AddEvent(object sender, EventArgs e)
        {
            AddEventData ad = (AddEventData)e;
            int c = ad.a + ad.b;
            Console.WriteLine("触发事件AddEvent, a+b={0}", c);
            return c;
        }
    }

    public class Test
    {
        // 事件委托，即事件原型定义
        public delegate int AddEventDelegate(object sender, EventArgs e);

        // 事件对象
        public event AddEventDelegate OnAddEvent = null;

        // 初始化事件
        public void InitAddEvent(AddEventDelegate addEvent)
        {
            this.OnAddEvent = addEvent;
            //this.OnAddEvent += new AddEventDelegate(addEvent);
        }

        // 触发事件
        public void CallAddEvent()
        {
            if (OnAddEvent != null)
            {
                AddEventData ad = new AddEventData();
                ad.a = 1;
                ad.b = 99;
                OnAddEvent(this, ad);
            }
        }
    }

    // 事件参数,必须继承类EventArgs
    public class AddEventData:EventArgs
    {
        public int a;
        public int b;
    }
}