工厂方法模式

// 工厂方法模式.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include<iostream>
using namespace std;
//抽象产品
class fruit
{
public:
	fruit();
	virtual ~fruit();
	//由于此类是抽象类，没有价格，所以只能将价格显示定义为纯虚函数
	virtual void show_price()=0;
};
fruit::fruit()
{}
fruit::~fruit()
{}

//具体产品1
class apple :public fruit
{
public :
	apple();
	virtual ~apple();
	virtual void show_price();
};
apple::apple()
{
	cout<<"i am an apple"<<endl;
}
apple::~apple()
{}
void apple::show_price()
{
	cout<<"my price is 5"<<endl;
}

//具体产品2
class orange :public fruit
{
public :
	orange();
	virtual ~orange();
	virtual void show_price();
};
orange::orange()
{
	cout<<"i am an orange"<<endl;
}
orange::~orange()
{}
void orange::show_price()
{
	cout<<"my price is 6"<<endl;
}
//工厂抽象类
//输入要创建实例的编号，创建对应实例，1：apple，2：orange
class fruit_factory
{
public:
	fruit_factory(){}
	~fruit_factory(){}
	virtual fruit *creat_fruit()=0;
};
//apple工厂类
class apple_factory:public fruit_factory
{
public:
	apple_factory(){}
	~apple_factory(){}
	virtual fruit * creat_fruit()
	{
	    return new apple;
	}
};

//orange工厂类
class orange_factory:public fruit_factory
{
public:
	orange_factory(){}
	~orange_factory(){}
	virtual fruit * creat_fruit()
	{
	    return new orange;
	}
};
int _tmain(int argc, _TCHAR* argv[])
{
	orange_factory chengzi_f;
	fruit *chengzi;
	chengzi=chengzi_f.creat_fruit();
	(*chengzi).show_price();
	return 0;
}