图书管理系统-实体对象ER图1

Requset

+T Amount

+ Requset(T){Amount=T;}

astractHandeler

+ astractHandeler nexthandle+string Name { get; set; }

+ astract handlerrequest(Request r)public Approver(string name) { this.Name = name; }

ConcreteHandeler3

ConcreteHandeler1(name):base(name)+ overwrite handlerrequest(Request r){ if(r.T????){判断能不能处理i canhandle it 没有elese结束{name}处理了}else if (nexthandle != null)//不能，转下一家 { nexthandle.handlerrequest(r); }}

main(){ConcreteHandeler1 c1=new ConcreteHandeler1();ConcreteHandeler1 c2=new ConcreteHandeler2();ConcreteHandeler1 c3=new ConcreteHandeler3();c1.nexthandle=c3;c3.nexthandle=c2;Requset re1=new Requset(1000); Requset re2=new Requset(3000); 不同的请求，谁最后确认是不一样的c1.handlerrequest(re1);c1.handlerrequest(re2);print(re1.amount);print(re2.amount);}完成！

ConcreteHandeler1

ConcreteHandeler1(name):base(name)+ overwrite handlerrequest(Request r){ if(r.T????){判断能不能处理i canhandle it 没有elese结束{name}处理了}else if (nexthandle != null) //不能，转下一家 { nexthandle.handlerrequest(r); }}

ConcreteHandeler2

ConcreteHandeler1(name):base(name)+ overwrite handlerrequest(Request r){ if(r.T????){判断能不能处理i canhandle it 没有elese结束{name}处理了}else if (nexthandle != null)//不能，转下一家 { nexthandle.handlerrequest(r); }}