C# 委托现实范例代码

using System;
using System.Collections.Generic;
using System.Text;
namespace Delegate {
    // 热水器
    public class Heater {
       private int temperature;
       public delegate void BoilHandler(int param);   //声明委托
       public event BoilHandler BoilEvent;        //声明事件
       // 烧水
       public void BoilWater() {
           for (int i = 0; i <= 100; i++) {
              temperature = i;
              if (temperature > 95) {
                  if (BoilEvent != null) { //如果有对象注册
                      BoilEvent(temperature);  //调用所有注册对象的方法
                  }
              }
           }
       }
    }
    // 警报器
    public class Alarm {
       public void MakeAlert(int param) {
           Console.WriteLine("Alarm：嘀嘀嘀，水已经 {0} 度了：",param);
       }
    }
    // 显示器
    public class Display {
       public static void ShowMsg(int param) { //静态方法
           Console.WriteLine("Display：水快烧开了，当前温度：{0}度。",param);
       }
    }
      
    class Program {
       static void Main() {
           Heater heater = new Heater();
           Alarm alarm = new Alarm();
           heater.BoilEvent += alarm.MakeAlert;    //注册方法
           heater.BoilEvent += (new Alarm()).MakeAlert;   //给匿名对象注册方法
           heater.BoilEvent += Display.ShowMsg;       //注册静态方法
           heater.BoilWater();   //烧水，会自动调用注册过对象的方法
       }
    }
}