庖丁解牛看委托和事件（续）

上一篇文章：庖丁解牛——深入解析委托和事件之后，以一题面试题来总结事件

 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;

namespace CallChange
{
    public class Call
    {
        static void Main(string[] args)
        {
            MessageMonitoring mm = new MessageMonitoring();
            //添加监听事件的响应函数
            mm.OnValueChange += new MMEventHandle((s, e) =>
            {

                Console.WriteLine(e.Value);

            });
            mm.Run();

        }
    }
    //参数e
    public class MMEventArgs : EventArgs
    {
        public int Value { get; set; }
    }
    public delegate void MMEventHandle(object sender, MMEventArgs e);
    //信息监控的类,当Value改变的时候，出发事件OnValueChange
    public class MessageMonitoring
    {
        public event MMEventHandle OnValueChange;
        private int _value;


        public void Run()
        {
            Thread thread = new Thread(() =>
            {
                while (true)
                {
                    Thread.Sleep(1000);
                    ++Value;
                }

            });
            thread.Start();

        }


        //属性改变
        public int Value
        {
            get { return _value; }
            set
            {
                if (_value != value)
                {
                    _value = value;
                    if (OnValueChange != null)
                    {
                        OnValueChange(this, new MMEventArgs { Value = _value });
                    }
                }
            }
        }

    }
}