设计模式中的备忘录模式解析及相关C++实例应用

#include <iostream> 
#include <string> 
using namespace std; 
 
class Memento 
{ 
private: 
  string state; 
 
public: 
  Memento(string state) 
    :state(state) 
  {} 
  string GetState() 
  { 
    return state; 
  } 
  void SetState(string state) 
  { 
    this->state = state; 
  } 
}; 
 
class CareTaker 
{ 
private: 
  Memento *memento; 
 
public: 
  void SetMemento(Memento *memento) 
  { 
    this->memento = memento; 
  } 
  Memento* GetMemento() 
  { 
    return this->memento; 
  } 
}; 
 
class Originator 
{ 
private: 
  string state; 
   
public: 
  Originator(string state) 
  { 
    this->state = state; 
  } 
 
  void RestoreMemento(Memento *memento) 
  { 
    state = memento->GetState(); 
  } 
 
  Memento *CreateMemento() 
  { 
    return new Memento(state); 
  } 
 
  void SetState(string state) 
  { 
    this->state = state; 
  } 
 
  void ShowState() 
  { 
    cout<< this->state <<endl; 
  } 
}; 
 
int main() 
{ 
  Originator *originator = new Originator("2012年11月11日，光棍节，一个人，没有女朋友"); 
  CareTaker *caretaker = new CareTaker(); 
  caretaker->SetMemento(originator->CreateMemento()); 
   
  cout<<"2012年11月11日，光棍节早晨的状态是："<<endl; 
 
  originator->ShowState(); 
 
  originator->SetState("中午参加同学婚礼去了，锦府盐帮饭店"); 
  originator->ShowState(); 
 
  cout<<"晚上回来的状态是"<<endl; 
  originator->RestoreMemento(caretaker->GetMemento()); 
  originator->ShowState(); 
 
  cout<<"跟早晨一样，嗨"<<endl; 
 
  system("pause"); 
  return 0; 
}