C#中的委托和事件

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

               }

        }

 }