c++ access error reading - c++

Question

#include<iostream>
using namespace std;
#include<conio.h>
#include<string>
#include <fstream>
#include <time.h>
#define KB_UP 72
#define KB_DOWN 80
#define KB_LEFT 75
#define KB_RIGHT 77
#define KB_ESCAPE 27
#define KB_ENTER 13
struct kimlik {
int id;
string TC;
string Ad;
string Soyad;
bool cinsiyet;
string dogumgunu;
string tel;
string eposta;
string girist;
string cıkıst;
int depozito;
int odenmis_k[12];
double endeks[12];
double fatura[12];
int oda_no;
};
struct kimlik kisi[20];
kisi is struct ^
I think error is under this row
void oku() {
cout << "okuma islemi yapiliyor";
ifstream file2;
file2.open("kisi.txt", ios::in | ios::binary );
file2.seekg(0L, ios::beg);
for (int i = 0; i < 20; i++) {
int i = 0;
cout << "suanda cursor " << file2.tellg() << endl;
file2.read((char *)&kisi[i], sizeof(kisi[i]));
}
I close the file
file2.close();
cout << "Islem tamamlandi";
getchar();
}
int main() {
if use don't use oku() there aren't any error
oku();
I am using oku
donus:
system("cls");
int i = 1;
int KB_code = 0;
string menu[7] = { " ","Kisi ekle","Kisi sil","Kisi duzenle","Listeleme
1","Listeme 2","Cikis" };
while ((KB_code != KB_ESCAPE) && (KB_code != KB_ENTER))
{
system("cls");
for (int c = 1; c <= 6; c++) {
if (c == i)
cout << ">> " << menu[c] << endl;
else
cout << " " << menu[c] << endl;
}
KB_code = _getch();
switch (KB_code)
{
case KB_DOWN:
i++;
if (i == 7)
i = 1;
cout << endl << i << endl;
break;
case KB_UP:
i = i - 1;
if (i == 0)
i = 6;
cout << endl << i << endl;
break;
}
}
if (KB_code == KB_ESCAPE)
goto bitir;
switch (i)
{
case 1:
system("cls");
kisi_ekle();
break;
case 2:
cout << "case2";
break;
case 3:
cout << "case3";
break;
case 4:
system("cls");
listeleme1();
break;
case 5:
cout << "case5";
break;
default:
goto bitir;
break;
}
_getch();
goto donus;
bitir:
system("pause");
program is working here and I push any key to close the console I take an error
}
I shared my project
error is at void oku() beacuse when I don't use it there aren't any error.
if I use oku(); when program finished, I take an access error reading error
_Pnext, 0xA3EF54

Answer 1

Your struct kimlik has members of type std::string. You cannot simply read data from a file into a struct holding std::string, because std::string manages it's data internally. Depending on the implementation an std::string has a pointer to some data and members for data size and string length. Your code simply writes into those values, thus creating corrupt std::strings with dangling pointers and invalid internal states. You need to write and read each string independently using the << and >> stream operators.
It's best to make your struct a class and create writeToStream() and readFromStream() methods in it:
class Kimlik {
public:
// constructor etc.
bool readFromStream(std::istream& s) {
// implement reading of each member here
// return true or false depending on whether reading succeeded or not
}
bool writeToStream(std::ostream& s) {
// implement writing of each member here
// return true or false depending on whether writing succeeded or not
}
private:
int id;
std::string TC;
std::string Ad;
std::string Soyad;
bool cinsiyet;
std::string dogumgunu;
std::string tel;
std::string eposta;
std::string girist;
std::string cıkıst;
int depozito;
int odenmis_k[12];
double endeks[12];
double fatura[12];
int oda_no;
};
Then use those methods where applicable:
kisi[i].readFromStream(file2);
Also see How to read and write a STL C++ string?