c++ - Binary files with Struct, classes, fstream error -

i have question regarding assignment have.

here have 2 of classes, employee class , gm class

void gm::addemployee(fstream& afile, int noofrecords) {     afile.open("employeeinfo.dat", ios::in | ios::binary);            employee::einfo e;         employee emp;     char name[80];     cout << "\nadd employee info" << endl;     cout << "---------------------" << endl;     cout << "new employee username: ";         cin.clear();         cin.ignore(100, '\n');     cin.getline(name, 80);         //check if there entry inside file name.         //if yes, add fail     bool flag = true;     if(noofrecords > 0)     {         for(int i=1; i<=noofrecords; i++)         {                afile.read (reinterpret_cast <char *>(&e), sizeof(e));             if(!strcmp(name, e.username))             {                 cout << "username used, add gm failed" << endl;                 flag = false;             }         }      }      afile.close();          if(flag)         {              //open in appending mode              afile.open("employeeinfo.dat", ios::out | ios::app | ios::binary);              strcpy(e.username, name);              cout << "please enter new employee's password: ";              cin.getline(e.password, 80);              cout << "\nplease enter new employee's appointment "                   << "\n(0 = gm / 1 = hm / "                   << "2= bs / 3 = fos)\n : ";              cin >> e.eid;              cin.clear();              cin.ignore(100, '\n');              emp.dist = strlen(e.password);              emp.caesar_encrypt(e.password, 3, emp.dist);              afile.write(reinterpret_cast <const char *>(&e), sizeof(e));          afile.close();               cout << "\nemployee added" << endl;         }  } 

the above function gm class, add employees.

i have declared structure in employee class as

struct einfo {     char username [80];     char password [80];     int eid; };  

the problem way of doing, when try add employee employeeinfo.dat data disappears. becomes blank after used add employee function.

can guide me on did wrong?

this wrong way read data e:

afile.read(reinterpret_cast<char*>(&e), sizeof(e)); 

likewise, wrong way write data e:

afile.write(reinterpret_cast<const char*>(&e), sizeof(e)); 

if need print or read data members of e, need 1 @ time. moreover, using read/write in context unecessary because use extractor , inserter:

afile >> e.username; // ... afile << e.username << e.password;