Thread: how can i read data from file... plz help me

Code:

out.read(reinterpret_cost < char * > ( &e ), sizeof (node ));

Typo?

What does an "e" object look like (in terms of data members)? How many "records" are you looking into when you do the first read/print (what is ID at that point) and how many total records are there in the file? Is the file attached to the out stream object binary/text and can you verify from looking at the file itself whether there is data at the start of the file? What specifically is the output being produced in both instances?

What compiler are you using and what (if any) warnings are present during compilation/linking?

sorry , my type here is wrong
node is my class so the e is the name to call the class
int main ()
{
node e ;
...
...
..
}

Code:

int main () 
{
	 node w ;
	total q;
nade e;
char op;
int id ,c,m;
long int pass;
	 
ifstream out;
out.open("out.dat",ios::binary);
	  if (!out )
	  {
		  cout << "  file could not be opened ... " << endl;
		  exit(1);
	  }
	  do {
		  n--;
		  cout << "enter the id : \a";
		  cin >> id;
		 cout << " entar your password:\a";
		 cin >> pass;

		 out.seekg((id) * sizeof(node),ios::beg);
		  out.read(reinterpret_cast <char * > ( &(w)) , sizeof (node ));


w.print();

		  if ( !(w.getpass()==pass))
		  {
cout << " your password is wrong ";
		  }
	 else
	 {


 ifstream out ;
	  out.open("out.r",ios::binary);
	  if (!out )
	  {
		  cout << "  file could not be opened ... " << endl;wait(1);
		 exit(1);
	  }

for ( int i =0 ;i<3;i++)
{
 out.seekg((i+1) * sizeof(nade),ios::beg);
		  out.read(reinterpret_cast <char * > ( &(e)) , sizeof (nade ));
		  	e.print();
}			 w.print();
       
			
						  cout << endl;
			  system("CLS")	;

cout << " do you want to continue  ( y \n )" << endl;
cin >> op; }while (op!='n'&&op !='N');



out.clear();
out.seekg(0);

for ( int i =0 ;i<3;i++)
{
 out.seekg((i+1) * sizeof(nade),ios::beg);
		  out.read(reinterpret_cast <char * > ( &(e)) , sizeof (nade ));
		  	e.print();
}
	  return 0;
}

in the first time the data is ok
but in the next thre are no output