委托和事件

而在写程序中，假设程序员就是老板，有两个类分别为主管和员工，而主管小王和员工小张就是两个类的对象实例。员工类有一个方法：玩游戏，同时就有一个玩游戏的事件，他一玩游戏就会激发这个事件。而主管类就是负责处理该事件的，他负责把玩游戏的员工的薪水扣除500。
public class Employee
 {

  public event PlayGameHandler   PlayGame;

  private int m_salary;
  
  public Employee()
  {
   Console.WriteLine("create a employee!");
   m_salary = 2000;
  }

  public int salary
  {
   get{return this.m_salary;}
   set{m_salary=value;}
  }
  public void EmployeePlayGame()
  {
      Console.WriteLine("begin  play game!");
   System.EventArgs e = new System.EventArgs();
   OnPlayGame(e);
  }

  protected virtual void OnPlayGame(EventArgs e)
  {
   if(PlayGame!=null)
   {
      PlayGame(this,e);
   }
  }

     }











public delegate void PlayGameHandler(object sender,System.EventArgs e);

 public class Manager
 {
  public Manager()
  {
    Console.WriteLine("create a manager!");
  }

  public void CutSalary(object sender,EventArgs e)
  {
     Console.WriteLine("begin cut");
     Employee  ely = (Employee)sender;
     ely.salary = ely.salary -100;
           Console.WriteLine("end cut");
  }
 }







class Class1
 {
  /// <summary>
  /// 应用程序的主入口点。/// </summary>
  [STAThread]
  static void Main(string[] args)
  {
    Console.WriteLine("scene begin..........");
    Manager m = new Manager();
    Employee ely = new Employee();
    ely.PlayGame += new PlayGameHandler(m.CutSalary);
   Console.WriteLine("salary is "+ely.salary.ToString()+"");
   Console.WriteLine("play game");
   Console.WriteLine();
   Console.WriteLine();
   Console.WriteLine();

   ely.EmployeePlayGame();
   Console.WriteLine("salary is "+ely.salary.ToString()+"");
   Console.WriteLine("scene is over");
   Console.ReadLine();

  }
 }