通俗粗暴的事件委托理解

简单粗暴的事件委托理解代码 

using System;
using System.Collections.Generic;

public class MyClass
{
    public static void RunSnippet()
    {
        Header head=new Header();
        XiaShuA xiashuaA=new XiaShuA(head);
        XiaShuB xiashuaB=new XiaShuB(head);
        head.Raise("左");
        Console.WriteLine("================================");
        head.Raise("右");
        Console.WriteLine("================================");
        head.Fall();
        Console.ReadLine();
    }
    
    #region Helper methods
    
    public static void Main()
    {
        try
        {
            RunSnippet();
        }
        catch (Exception e)
        {
            string error = string.Format("---
The following error occurred while executing the snippet:
{0}
---", e.ToString());
            Console.WriteLine(error);
        }
        finally
        {
            Console.Write("Press any key to continue...");
            Console.ReadKey();
        }
    }

    private static void WL(object text, params object[] args)
    {
        Console.WriteLine(text.ToString(), args);    
    }
    
    private static void RL()
    {
        Console.ReadLine();    
    }
    
    private static void Break() 
    {
        System.Diagnostics.Debugger.Break();
    }

    #endregion
}


public     delegate void RaiseEventHandler(string hand);
public delegate void FallEventHandler();

public class Header
{
    public event RaiseEventHandler RaiseEvent;
    public event FallEventHandler FallEvent;
    
    public void Raise(string hand)
    {
        Console.WriteLine("首领 {0} 手举杯",hand);
        if(RaiseEvent!=null)
        {
            RaiseEvent(hand);
        }
    }
    
    public void Fall()
    {
        Console.WriteLine("首领摔杯");
        if(FallEvent !=null)
        {
            FallEvent();
        }
    }
}

public class XiaShuA
{
    Header header;
    public XiaShuA(Header _head)
    {
        this.header=_head;
        this.header.RaiseEvent+=new RaiseEventHandler(FallRaise);
        this.header.FallEvent+=new FallEventHandler(Fallhand);
    }
    
    public void FallRaise(string hand)
    {
        if(hand=="左")
        {
            Attach();    
        }
    }
    public void Fallhand()
    {
        Attach();
    }
    
    public void Attach()
    {
        Console.WriteLine("xiashuA立即攻击");
    }
}

public class XiaShuB
{
    Header header;
    public XiaShuB(Header _head)
    {
        this.header=_head;
        this.header.RaiseEvent+=new RaiseEventHandler(FallRaise);
        this.header.FallEvent+=new FallEventHandler(Fallhand);
    }
    
    public void FallRaise(string hand)
    {
        if(hand=="右")
        {
            Attach();    
        }
    }
    public void Fallhand()
    {
        Attach();
    }
    
    public void Attach()
    {
        Console.WriteLine("xiashubB立即攻击");
    }
}