前言

责任链模式通过将请求和处理者解耦，关联多个处理者形成一个链条，使每个处理者都有机会处理请求，避免了将所有处理逻辑集中在一个对象中的复杂性。

代码

//请求者
public class Requestor
{private string content;public string Content { get { return content; } }public Requestor(string content) {this.content = content;}
}
//处理者
public abstract class Handler
{public abstract void SetNext(Handler handler);public abstract void HandleRequest(Requestor requestor);
}
//处理者:接收者A
public class ReceiverA : Handler
{private Handler nextHandler;public override void SetNext(Handler handler){nextHandler = handler;}public override void HandleRequest(Requestor requestor){if (requestor.Content.Equals("A")) {Console.WriteLine("receiverA handle the request...");}else if(nextHandler!=null){nextHandler.HandleRequest(requestor);}}
}
//处理者:接收者B
public class ReceiverB : Handler
{private Handler nextHandler;public override void HandleRequest(Requestor requestor){if (requestor.Content.Equals("B")){Console.WriteLine("receiverB hanlde the request...");}else if (nextHandler != null){nextHandler.HandleRequest(requestor);}}public override void SetNext(Handler handler){this.nextHandler = handler;}
}/** 行为型模式：Behavioral Pattern* 责任链模式： Chain-of-responsibility Pattern*/
internal class Program
{static void Main(string[] args){//创建接收请求Handler handlerA = new ReceiverA();Handler handlerB = new ReceiverB();//设置下一个请求处理者handlerA.SetNext(handlerB);//创建请求者A，并处理请求Requestor receiverA = new Requestor("A");handlerA.HandleRequest(receiverA);Requestor receiverB = new Requestor("B");handlerA.HandleRequest(receiverB);Requestor requestorC = new Requestor("C");handlerA.HandleRequest(requestorC);Requestor receiverA2 = new Requestor("A");handlerA.HandleRequest(receiverA2);Console.ReadLine();}
}

运行结果