委托模式的应用

public class Manage
{
//声明委托
public delegate void EventHandler(string a);
//声明事件
public event EventHandler Change;
public void RaiseEvent(string a)
{
Change(a);
}
}

public class Action
{
public static void doA()
{
Console.WriteLine("doA");
}

public static void doB()
{
Console.WriteLine("doB");
}

public static void doC()
{
Console.WriteLine("doC");
}
}

static void Main(string[] args)
{
Manage m = new Manage();
//注册事件
m.Change += new Manage.EventHandler(m_Change);
Action.doA();
//当调用doA()方法时,触发事件,通知doA()方法被调用
m.RaiseEvent("doA");
//触发事件时的具体操作
static void m_Change(string a)
{
switch(a)
{
case "doA":
break;
case "doB":
break;
case "doC":
break;
default:
break;
}
}
}