Binary file- obj(game) save and load the obj

Question

this copy this address(i dont whant to copy address )and then I release the first object All Course This exercise class I have to realize saving and loading the game Treasure Hunt

My files : Main :

srand(time(0));
TreasureSeeker dudu;
int save = 0;
cout << "To New game prees 1 to load game prees 2 : ";
cin >> save;
while (save !=1 &&save !=2 )
{
    cout << "To New game prees 1 to load game prees 2 : ";
    cin >> save;
}
if (save == 1)
{
    ifstream inFile("try.dat", ios::binary);
    TreasureSeeker temp(inFile);
    inFile.close();
    temp.play();
}
else
{
    dudu.setname();
    dudu.play();
    ofstream outFile("try.dat", ios::binary | ios::trunc);
    dudu.save(outFile);
    outFile.close();
}

and':

#define _CRT_SECURE_NO_WARNINGS
#ifndef _TreasureSeeker_H
#define _TreasureSeeker_H
#include "GamePiece.h"
#include "Player.h"
#include "Treasure.h"
#include"Enemy.h"
#include"Trap.h"

using namespace std;

//class Treasusekeer

class TreasureSeeker 
{
public:
    TreasureSeeker();
    ~TreasureSeeker();
    void play();
    void save(ofstream & out)const;
    TreasureSeeker(ifstream& in);
    void setname();
private:
    Player *p1;//obj to player
    Treasure* t1;//obj to Treasure
    Trap *trap1;//obj to Trap
    Enemy *en1;//obj to Enemy
    GamePiece borad[9][9];
    GamePiece *emp1;//obj empty
    GamePiece temp;//obj temp to save for a enemy move
    void check(int flag);

    void print();
    void del();
    void check(int i, int j, int move);
    void step();
    void checkenemy(int p);
};

#endif

This is the Func to copy :

void TreasureSeeker::save(ofstream & out)const
{
    out.write((const char*)this, sizeof(*this));
}

TreasureSeeker::TreasureSeeker(ifstream& in)
{
    in.read((char*)this, sizeof(*this));
}

player :

#include "GamePiece.h"
#ifndef _Player_H
#define _Player_H

//class player

class Player : public GamePiece
{

public:

    Player();
    ~Player();
    void print();
    int Neutralization();
    int Step();
    int getX(){ return this->placeX; }
    int getY(){ return this->placeY; }
    void setx(int x){this->placeX = x;}
    void sety(int y){this->placeY = y;}
    void fight();
    void findknife();
    void setn(string d){ this->nameplayer = d; }

private:
    string nameplayer;
    int knife;
    int placeX;
    int placeY;
    int killenemy;
    int killtrap;

};
#endif

trap :

#include"GamePiece.h"
#ifndef _Trap_H
#define _Trap_H

class Trap :public GamePiece
{
public:
    Trap();
    ~Trap();
    void puttrap(int x,int y);
    int getnumoftrap();
private:
    int numoftrap;
};

#endif

and Treasure :

#include"GamePiece.h"
#ifndef _Treasure_H
#define _Treasure_H
class Treasure :public GamePiece
{
public:
    Treasure(int x, int y);
    ~Treasure();
    int getX();
    int getY();
    int Gettrusefake();

private:
    int TreasureX;
    int TreasureY;
    int Treasurefake;
};

#endif

and the borad is from this class :

#define _CRT_SECURE_NO_WARNINGS
#ifndef _GamePiece_H
#define _GamePiece_H
#include <iostream>
#include <string>
#include <cstring>
#include <fstream>
#include <ctype.h>
#include <time.h> 
#include <typeinfo>
#include <stdlib.h> 
using namespace std;

//class gamepiece +func get set print 

class GamePiece
{
public:
    GamePiece(){ nametool = "Empty Cell"; charname = 'O'; }
    ~GamePiece(){};
    void printname(){ cout << "name tool is :" << nametool << endl; }
    void printchar(){ cout << charname; }
    virtual void step(){};
    char getname(){ return charname; }
    string getoolname(){ return nametool; }
    void setcharname(char p){ charname = p; }



private:
    string nametool;
    char charname;
};

#endif

and this is the func to play :

    cout << "Hello to Find the Treasure game" << endl;
    int save = 1;

    do
    {
        cout << endl;
        p1->print();
        cout << endl;
        print();
        step();
        cout << endl;
        print();
        cout << "to save end exit prees 0 to continue prees 1 :" << endl << " your choise : ";
        cin >> save;
    } while (save);

}

Is this question encrypted? Anyone knows what the private key is? — Sam Varshavchik, Sep 04 '16 at 16:07
What makes you think you can simply serialize your class to a file and retrieve it back later on? The pointers can't be recreated. — πάντα ῥεῖ, Sep 04 '16 at 16:08
so can u guide me what to do than i can Saving and loading the game please? — Dudu Moyal, Sep 04 '16 at 16:14
Since this is an exercise for a course, everything you need to know should be covered in the course materials. — molbdnilo, Sep 04 '16 at 16:16
Article cyber) selection - 10 points (: There implement saving and loading of the game, use the binaries. — Dudu Moyal, Sep 04 '16 at 16:22
@Dudu Moyal, you do not have to post the whole code! See [MCVE](http://stackoverflow.com/help/mcve) — WhiZTiM, Sep 04 '16 at 16:32

score 3 · Accepted Answer · edited May 23 '17 at 10:33

void TreasureSeeker::save(ofstream & out)const
{
    out.write((const char*)this, sizeof(*this));
}

You may only do this if all the data members of the class are POD types and do not own a resource, even with that, there comes the issue of structure padding.

Free advice, don't do this expressly, its usually not portable even for non-resource owning POD types.

NOTE: A pointer either owns or refers to a resource (memory).

Different compilers may pad your structure and lay it out in memory differently.

TreasureSeeker::TreasureSeeker(ifstream& in)
{
    in.read((char*)this, sizeof(*this));
}

In addition to what I said previously, this is also a pretty bad idea. You are in the context of this, and externally modifying the whole of this, while its alive....

To solve your problem, read About Serialization in C++

Binary file- obj(game) save and load the obj

1 Answers1