策略模式C++代码示例---《大话设计模式》笔记

-------------------------------------------------------------------------------------------------------------

#pragma once

#include <string>

using namespace std;

//基类

class CashSuper

{

public:
virtual double GetCash(double money){return money;}

};

//子类

class CashNormal:public CashSuper

{
virtual double GetCash(double money){return money;}

};

class CashRebate:public CashSuper

{

private:
double Rebate;

public:
CashRebate(string re)
{
Rebate=atof(re.c_str());
}
virtual double GetCash(double money){return money*Rebate;}

};

class CashReturn:public CashSuper

{

private:
double moneyCondition;
double moneyReturn;

public:
CashReturn(string mc,string mr)
{
moneyCondition=atof(mc.c_str());
moneyReturn=atof(mr.c_str());
}
virtual double GetCash(double money)
{
int count=money/moneyCondition;
return money-count*moneyReturn;
}
};

-------------------------------------------------------------------------------------------------------------

#include <string>

#include "CashSuper.h"

using namespace std;

class Strategy

{

protected:
CashSuper *cs;

public:
Strategy(string type)
{
if(type=="正常收费")
cs=new CashNormal();
if(type=="满300减100")
cs=new CashReturn("300","100");
if(type=="打8折")
cs=new CashRebate("0.8");
}
double GetResult(double money)
{
return cs->GetCash(money);
}

};

-------------------------------------------------------------------------------------------------------------

#include "Strategy.h"

#include <iostream>

using namespace std;

int main()

{

int price=200;
int num=5;
string type="打8折";//"满300减100",或者 "正常收费"

Strategy cs(type);
cout<<cs.GetResult(price*num);
system("pause");
return 0;

}