：裝飾者模式--Beverage

#ifndef __BEVERAGE_H__
#define __BEVERAGE_H__
#include <string>
using namespace std;
class Beverage
{
public:
	Beverage()
	{
	}
	virtual ~Beverage(){}
	virtual string getDescripthion()
	{
		return  "Unknown Beverage";
	}
	virtual float cost() = 0
	{

	}
};


class Espresso :public Beverage
{
public:
	Espresso()
	{
	
	}
	virtual ~Espresso(){}
	virtual float cost()
	{
		return 1.99f;
	}
	virtual string  getDescripthion()
	{
		return  "Espresso";
	}
};

class HouseBlend :public Beverage
{
public:
	HouseBlend(){}
	virtual ~HouseBlend(){}
	virtual float cost()
	{
		return 0.89;
	}
	virtual string getDescripthion()
	{
		return "HouseBlend";
	}
};



#endif

#ifndef __DECORATOR_H__
#define __DECORATOR_H__

#include "Beverage.h"
class Decorator : public Beverage
{
public:
	Decorator(){}
	virtual ~Decorator(){}
	virtual string getDescripthion() = 0
	{

	}
	virtual float cost() = 0
	{

	}
};

class Mocha : public Decorator
{
private:
	Beverage *beverage;
public:
	Mocha(Beverage *b)
	{
		beverage = b;
	}
	virtual ~Mocha(){}
	virtual  string  getDescripthion()
	{
		return beverage->getDescripthion() + ", Mocha";
	}
	virtual float cost()
	{
		return beverage->cost() + 0.20;
	}
};

class Soy : public Decorator
{
private:
	Beverage *beverage;
public:
	Soy(Beverage *b)
	{
		beverage = b;
	}
	virtual ~Soy(){}
	virtual  string  getDescripthion()
	{
		return beverage->getDescripthion() + ", Soy";
	}
	virtual float cost()
	{
		return beverage->cost() + 0.15;
	}
};

class Whip : public Decorator
{
private:
	Beverage *beverage;
public:
	Whip(Beverage *b)
	{
		beverage = b;
	}
	virtual ~Whip(){}
	virtual  string  getDescripthion()
	{
		return beverage->getDescripthion() + ", Whip";
	}
	virtual float cost()
	{
		return beverage->cost() + 0.10;
	}

};

#endif

#include <iostream>
#include "Decorator.h"

using namespace std;
int main()
{
	Beverage *ber = new Espresso();
	cout << ber->getDescripthion() << "+"<< ber->cost()<<endl;

	Beverage *ber2 = new HouseBlend();
	ber2 = new Soy(ber2);
	ber2 = new Mocha(ber2);
	ber2 = new Whip(ber2);
	cout << ber2->getDescripthion() << "+" << ber2->cost()<<endl;


	return 0;
}