file handling

[bnps]

while I am entering data all roll nubers are added to dat file accept roll no 26 . afetr entering 26 it is not storing any other record ? Help me ? Tell me the reason as well.

#include<conio.h>
#include<fstream.h>
class a
{
int r;
char nm[10];
public:
void in()
{    
cout<<"enter roll";
cin>>r;
cout<<"enter name";
cin>>nm;
}
void disp()
{
cout << nm;
cout<<r;
}
}a1;
void main()
{
clrscr();
char ans = 'y';
ofstream fout;
ifstream fin;
void create();
fout.open ("qw.dat",ios::out);
   do
   {
   a1.in();
   fout.write((char*)&a1,sizeof(a1));
   cout<<" more   ?  ";
   cin>>ans;
   }while (ans=='y');
 fout.close();
 fin.open("qw.dat",ios ::in);
 fin.read((char*)&a1,sizeof(a1));
 while(!fin.eof())
 { a1.disp();
   fin.read((char*)&a1,sizeof(a1));
   }
   fin.close();
   }

[weaknessforcats]

Start by not reading/writing sizeof(a1).

Write the individual members and read them back in the same order. Your file is in text mode. You might consider separating your values with a delimiter.

Writre a function to write one struct and one to read one struct.