Memento模式

将状态保存，很简单，看看就能懂

Memento.h

#ifndef _MEMENTO_H

#define _MEMENTO_H

#include <iostream>

#include <string>

using namespace std;

class Originator;

class Memento

{

public:

protected:

private:

friend class Originator;

Memento() {

}

Memento(const string& sdt) {

_sdt = sdt;

}

~Memento() {

}

void SetState(const string& sdt) {

_sdt = sdt;

}

string GetState() {

return _sdt;

}

private:

string _sdt;

};

class Originator

{

public:

Originator() {

_sdt = "";

_mt = NULL;

}

Originator(const string& sdt) {

_sdt = sdt;

_mt = NULL;

}

~Originator() {

}

Memento* CreateMemento() {

return new Memento(_sdt);

}

string GetState() {

return _sdt;

}

void SetState(const string& sdt) {

_sdt = sdt;

}

void PrintState() {

cout << _sdt << endl;

}

void SetMemento(Memento* men) {

_mt = men;

}

void RestoreToMemento(Memento* mt) {

_sdt = mt->GetState();

}

private:

string _sdt;

Memento* _mt;

};

#endif // _MEMENTO_H

Memento.cpp

#include "Memento.h"

int main()

{

Originator* o = new Originator;

o->SetState("old");

o->PrintState();

Memento* m = o->CreateMemento();

o->SetState("new");

o->PrintState();

o->RestoreToMemento(m);

o->PrintState();

return 0;

}

编译:make Memento