设计模式-装饰模式

来源：互联网发布：车载数据采集系统编辑：程序博客网时间：2024/05/29 09:27

网上的装饰模式学习资料有很多，下面是我的想法。

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装饰模式：

主要是一级一级向上的叠加，

一个关键的点是：第二级向下扩展第三级时，第三级返回的数要向上传递，

sum=0；sum+=2；sum+=3；有这样子的一种感觉。

//定义原蛋糕20元，奶油5元，加图案3元，加水果8元，加蜡烛4元，精美包装2元，卡片1元

//1蛋糕类class Cake{public:    virtual double addMoney() = 0;};//2_1原包装类class OriginalCake : public Cake{private:double OriginalPrice;//蛋糕原价格Cake *m_OriginalCake;public:OriginalCake(double price){OriginalPrice = price;}double addMoney(){return OriginalPrice;}//返回原价};//2_2包装class ExtraCake : public Cake{private:     Cake *m_ExtraCake;//蛋糕public:    ExtraCake(Cake *pCake) : m_ExtraCake(pCake){}    double addMoney(){        if (m_ExtraCake != NULL){            return  m_ExtraCake->addMoney();        }//如果没有额外添加，添加为0return 0;    }};//3_1加奶油class AddButter : public ExtraCake{private:double ButterPrice;//奶油价格public:    AddButter(Cake *pExtraCake,double price) : ExtraCake(pExtraCake){this->ButterPrice=price;}    double addMoney(){return ButterPrice+ExtraCake::addMoney();    }//        奶油钱+原价void SetButterPrice(double price){this->ButterPrice=price;}//设置价格};//3_2加图案class AddPattern : public ExtraCake{private:double PatternPrice;//图案价格public:    AddPattern(Cake *pExtraCake,double price) : ExtraCake(pExtraCake){this->PatternPrice=price;}    double addMoney(){return PatternPrice+ExtraCake::addMoney();    }//        图案钱+原价void SetPatternPrice(double price){this->PatternPrice=price;}//设置价格};//3_3加水果class AddFruit : public ExtraCake{private:double FruitPrice;//水果价格public:    AddFruit(Cake *pExtraCake,double price) : ExtraCake(pExtraCake){this->FruitPrice=price;}    double addMoney(){        return FruitPrice+ExtraCake::addMoney();    }////        水果钱+原价void SetFruitPrice(double price){this->FruitPrice=price;}//设置价格};//3_4加蜡烛class AddCandle : public ExtraCake{private:double CandlePrice;//蜡烛价格public:    AddCandle(Cake *pExtraCake,double price) : ExtraCake(pExtraCake){this->CandlePrice=price;}    double addMoney(){        return CandlePrice+ExtraCake::addMoney();    }////        蜡烛钱+原价void SetCandlePrice(double price){this->CandlePrice=price;}//设置价格};//3_5精美包装class AddCasing : public ExtraCake{private:double CasingPrice;//精美包装价格public:    AddCasing(Cake *pExtraCake,double price) : ExtraCake(pExtraCake){CasingPrice=price;}    double addMoney(){        return CasingPrice+ExtraCake::addMoney();    }////        蜡烛钱+原价void SetCasingPrice(double price){this->CasingPrice=price;}//设置价格};//3_6增加卡片class AddCard : public ExtraCake{private: double CardPrice;//卡片价格public:AddCard(Cake *pExtraCake,double price) : ExtraCake(pExtraCake){CardPrice=price;}double addMoney(){return CardPrice+ExtraCake::addMoney();}////        卡片钱+原价void SetCardPrice(double price){this->CardPrice=price;}//设置价格};int main(){//定义原蛋糕20元，奶油5元，加图案3元，加水果8元，加蜡烛4元，精美包装2元，卡片1元OriginalCake* _OCake = new OriginalCake(20);cout<<"原味："<<_OCake->addMoney()<<"元"<<endl;Cake *pCake1 = new AddButter(_OCake,5);cout<<"原味 + 奶油："<<pCake1->addMoney()<<"元"<<endl;Cake *pCake2 = new AddButter( new AddFruit(_OCake,8),5);cout<<"原味 + 奶油 + 水果："<<pCake2->addMoney()<<"元"<<endl;Cake *pCake3 = new AddButter( new AddFruit( new AddCandle(new AddCard(_OCake,2),4),8),5);cout<<"原味 + 奶油 + 水果 + 蜡烛 + 卡片："<<pCake3->addMoney()<<"元"<<endl;Cake *pCake4 = new AddPattern( new AddCasing(_OCake,2),3);cout<<"原味 + 图案 + 精美包装："<<pCake4->addMoney()<<"元"<<endl;delete _OCake; _OCake = NULL;delete pCake1; pCake1 = NULL;delete pCake2; pCake2 = NULL;delete pCake3; pCake3 = NULL;delete pCake4; pCake4 = NULL; return 0;}

//定义原蛋糕20元，奶油5元，加图案3元，加水果8元，加蜡烛4元，精美包装2元，卡片1元

1．原味，20：输出20元

2．原味 + 奶油，20+5：输出25元

3．原味 + 奶油+ 水果，20+8+5：输出33元

4．原味 + 奶油+ 水果 + 蜡烛 + 卡片：输出39元

5．原味 + 图案+ 精美包装：输出25元

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