设计模式 --> （13）备忘录模式

#include <iostream>
#include <vector>
using namespace std;

//需保存的信息  
class Memento    
{  
public:  
    int m_vitality; //生命值  
    int m_attack;   //进攻值  
    int m_defense;  //防守值  
public:  
    Memento(int vitality, int attack, int defense):   
      m_vitality(vitality),m_attack(attack),m_defense(defense){}  
    Memento& operator=(const Memento &memento)   
    {  
        m_vitality = memento.m_vitality;  
        m_attack = memento.m_attack;  
        m_defense = memento.m_defense;  
        return *this;  
    }  
};  

//游戏角色  
class GameRole    
{  
private:  
    int m_vitality;  
    int m_attack;  
    int m_defense;  
public:  
    GameRole(): m_vitality(100),m_attack(100),m_defense(100) {}  
    Memento Save()  //保存进度，只与Memento对象交互，并不牵涉到Caretake  
    {   
        Memento memento(m_vitality, m_attack, m_defense);  
        return memento;  
    }  
    void Load(Memento memento)  //载入进度，只与Memento对象交互，并不牵涉到Caretake  
    {  
        m_vitality = memento.m_vitality;  
        m_attack = memento.m_attack;   
        m_defense = memento.m_defense;  
    }  
    void Show() { cout<<"vitality : "<< m_vitality<<", attack : "<< m_attack<<", defense : "<< m_defense<<endl; }  
    void Attack() { m_vitality -= 10; m_attack -= 10;  m_defense -= 10; }  
};  
//保存的进度库  
class Caretake    
{  
public:  
    Caretake() {}  
    void Save(Memento menento) { m_vecMemento.push_back(menento); }  
    Memento Load(int state) { return m_vecMemento[state]; }  
private:  
    vector<Memento> m_vecMemento;  
};

//测试案例  
int main()  
{     
    Caretake caretake;  
    GameRole role;   
    role.Show();   //初始值  
    caretake.Save(role.Save()); //保存状态  
    role.Attack();     
    role.Show();  //进攻后  
    role.Load(caretake.Load(0)); //载入状态   
    role.Show();  //恢复到状态0  
    return 0;  
}