//5.工廠模式 //ver1 //回顧簡單工廠模式 class OperationFactory { public:static Operation createOperation(char chOper){Operation * op = NULL;switch(chOper){case '+':op = new OperationAdd();break;case '-':op = new OperationSub();break;default:break;}return *op;} };void main11() {Operation oper;oper = OperationFactory::createOperation('+');oper.SetNumberA(1.1);oper.SetNumberB(2.2);double result = oper.GetResult(); }//工廠模式: //工廠接口 class Operation { public:Operation(){}~Operation(){} protected:double _NumberA;double _NumberB; public:void SetNumberA(double A){_NumberA = A;}double GetNumberA(){return _NumberA;}void SetNumberB(double B){_NumberB = B;}double GetNumberB(){return _NumberB;}virtual double GetResult(){double result = 0;return result;} };class OperationAdd : public Operation { public:virtual double GetResult(){double result = _NumberA + _NumberB;return result;} };class OperationSub : public Operation { public:virtual double GetResult(){double result = _NumberA - _NumberB;return result;} };class IFactory { public:virtual Operation CreateOperation(){Operation * po = NULL;return *po;} };class AddFactory : public IFactory { public:virtual Operation CreateOperation(){Operation * po = new OperationAdd();return *po;} };class SubFactory : public IFactory { public:virtual Operation CreateOperation(){Operation * po = new OperationSub();return *po;} };void main1() {IFactory * pif = new AddFactory();Operation po = pif->CreateOperation();po.SetNumberA(1.1);po.SetNumberB(2.2);double result = po.GetResult(); }

?

//簡單工廠模式的最大優點在于工廠類中包含了必要的邏輯判斷，根據客戶端的選擇條件動態實例化相關的類，
//對于客戶端來說，去除了與具體產品的依賴。

//工廠模式，定義一個用于創建對象的接口，讓子類決定實例化哪一個類。工廠方法使一個類的實例化延遲到其子類。
//工廠模式實現時，客戶端需要決定實例化哪一個工廠來實現運算類，選擇判斷的問題還是存在，也就是說，工廠方式把
//簡單工廠的內部邏輯判斷移到了客戶端代碼來進行。你想要加功能，本來是改工廠類，現在是改客戶端。

?

//5.工廠模式 //ver2 class LeiFeng { public:void Sweep(){//打掃}void Wash(){//洗衣} };//學習雷鋒大學生 class Undergraduate : public LeiFeng {};//志愿者 class Volunteer : public LeiFeng {};//簡單雷鋒工廠 class SimpleFactory { public:static LeiFeng CreateLeiFeng(char cType){LeiFeng * plf = NULL;switch (cType){case '1': //大學生plf = new Undergraduate();break;case '2': //志愿者plf = new Volunteer();break;default:break;}return *plf;} };void main21() {LeiFeng stuA = SimpleFactory::CreateLeiFeng('1');stuA.Sweep();LeiFeng volA = SimpleFactory::CreateLeiFeng('2');volA.Wash(); }//雷鋒工廠 class IFactory { public://IFactory(){}LeiFeng CreateLeiFeng(){LeiFeng * plf = new LeiFeng();return *plf;} };//大學生工廠 class UndergraduateFactory : public IFactory { public://UndergraduateFactory(){}LeiFeng CreateLeiFeng(){LeiFeng *plf = new Undergraduate();return *plf;} };//志愿者工廠 class VolunteerFactory : public IFactory { public://VolunteerFactory(){}LeiFeng CreateLeiFeng(){LeiFeng * plf = new Volunteer();return *plf;} };void main22() {IFactory * pf = new UndergraduateFactory();LeiFeng stu = pf->CreateLeiFeng();stu.Sweep();stu.Wash(); }

?

//工廠模式客服了簡單工廠違背開放-封閉原則的缺點，又保持了封裝對象創建過程的優點。
//缺點:每加一個產品，就需要加一個產品工廠的類，增加了額外的開發量。

　

?

轉載于:https://www.cnblogs.com/sylar-liang/p/6025042.html

總結

以上是生活随笔為你收集整理的设计模式(5)--工厂模式的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。