四个角色：传递者接口(Handler)、具体传递者(ConcreteHandler)、客户端(Client)
传递者接口(Handler)：定义一个处理请求的接口和实现下一个对象
具体传递者(ConcreteHandler)：如果能够处理就处理，否则让上级处理请求
客户端(Client) ：创立责任链，并向链中对象提出请求
实现思路：传递者接口设置上级然后提供一个处理请求的方法，在具体传递中如果能够处理就处理，否则就让其上级来处理，客户端组织其责任链，并且设置请求。
类图：
应用场景：OA系统中的请假审批系统，普通开发者想请假，如果请1天及以下的假则只需要开发经理许可，如果1天<请假天数<=5天则需要总监许可，如果5天<请假天数<=10天则需要副总裁批准,如果请假天数>10天则需要总裁许可。
分析：在客户端设置责任链和请假审批的上级下级，然后每次普通开发者将请假申请提交到开发经理，如果在开发经理许可范围之内，则处理，否则提交给他的上级总监，以此类推处理这个请假请求。
下面我们在控制台程序去演示一下如何使用Chain of Responsibility Pattern：
一、 传递者接口(Handler)
- //传递者接口(Handler)
- abstract class Higher
- {
- public string Name { get; set; }
- public Higher higher;
- public void SetHigher(Higher _Higher)
- {
- this.higher = _Higher;
- }
- public Higher(string name)
- {
- Name = name;
- }
- public abstract void ExeApply(Apply apply);
- }
二、具体传递者(ConcreteHandler)
- //具体传递者(ConcreteHandler)
- class ManagerHigher : Higher
- {
- public ManagerHigher(string name) : base(name) { }
- public override void ExeApply(Apply apply)
- {
- if (apply.ApplyDay <= 1)
- Console.WriteLine(Name + " 批准 " + apply.ApplyName + " 申请了 " + apply.ApplyDay + "天假期");
- else
- higher.ExeApply(apply);
- }
- }
- //具体传递者(ConcreteHandler)
- class DirectorHigher : Higher
- {
- public DirectorHigher(string name) : base(name) { }
- public override void ExeApply(Apply apply)
- {
- if (apply.ApplyDay <= 5)
- Console.WriteLine(Name + " 批准 " + apply.ApplyName + " 申请了 " + apply.ApplyDay + "天假期");
- else
- higher.ExeApply(apply);
- }
- }
- //具体传递者(ConcreteHandler)
- class VPHigher : Higher
- {
- public VPHigher(string name) : base(name) { }
- public override void ExeApply(Apply apply)
- {
- if (apply.ApplyDay <= 10)
- Console.WriteLine(Name + " 批准 " + apply.ApplyName + " 申请了 " + apply.ApplyDay + "天假期");
- else
- higher.ExeApply(apply);
- }
- }
- //具体传递者(ConcreteHandler)
- class CEOHigher : Higher
- {
- public CEOHigher(string name) : base(name) { }
- public override void ExeApply(Apply apply)
- {
- if (apply.ApplyDay>10)
- Console.WriteLine(Name + " 批准 " + apply.ApplyName + " 申请了 " + apply.ApplyDay + "天假期");
- else
- higher.ExeApply(apply);
- }
- }
三、客户端(Client)
- class Program
- {
- static void Main(string[] args)
- {
- //责任链模式的创建
- Higher managerHigher = new ManagerHigher("张三经理");
- Higher directorHigher = new DirectorHigher("李四总监");
- Higher vpHigher = new VPHigher("王五副总裁");
- Higher ceoHigher = new CEOHigher("林一总裁");
- managerHigher.SetHigher(directorHigher);
- directorHigher.SetHigher(vpHigher);
- vpHigher.SetHigher(ceoHigher);
- //创建申请人
- Apply liuying = new Apply() { ApplyName = "刘颖", ApplyDay = 5 };
- Apply chenming = new Apply() { ApplyName = "陈明", ApplyDay = 1 };
- Apply zengli = new Apply() { ApplyName = "曾利", ApplyDay = 15 };
- //申请人都将申请提交给经理
- managerHigher.ExeApply(liuying);
- managerHigher.ExeApply(chenming);
- managerHigher.ExeApply(zengli);
- Console.ReadLine();
- }
- }
申请人
- //申请人
- class Apply
- {
- public string ApplyName { get; set; }
- public double ApplyDay { get; set; }
- }
如需源码请点击 ResponsibilityPattern.rar 下载。
本文转自程兴亮 51CTO博客，原文链接:http://blog.51cto.com/chengxingliang/827004
