Thread: Reading in the last few characters of a file problems

I've been working on a small bank-like program that writes to a file like this:

Opening Balance >>>>> $546.50
Deposit >>>>>> $52.50; New Balance: $599.00
Withdrawl >>>>>> $49.00; New Balance: $550.00

The writing to the file part works great, but when I re-open the file, I need to somehow grab the balance from the last time, otherwise I just start printing the last spot in memory when I call the function to display the balance (obviously). I am not really great with file manipulation yet (still learning a lot). Is there anyone who can give me an idea on how to grab the balance from the file when I open it again?

Thanks,
Dustin

here is a sample prog for yah

Code:

#include <iostream.h>
#include <fstream.h>

int main()
{
  ifstream inFile;
  char temp;
  float start_balance;

  inFile.open("bank.txt");
  while(inFile)
  {
    do
    {
      inFile >> temp;
    }while (temp!='$');
    inFile >> start_balance;
  }
  inFile.close();
  cout << "Last Balance was : $" <<start_balance;
  return 0;
}

and the bank.txt contains this:

Code:

Opening Balance >>>>>> $546.50 
Deposit >>>>>> $52.50; New Balance: $599.00
Withdrawl >>>>>> $49.00; New Balance: $550.00

cheers

Code:

#include <iostream.h>
#include <fstream.h>

main()
{
      int OpenBalance, Deposit, Withdrawal, NewBalance, NewBalanceTwo;

      ifstream fin;
      fin.open("bank.txt");
      fin<<OpenBalance;
      fin<<Deposit;
      fin<<Withdrawal;
      fin<<NewBalance;
      fin<<NewBalanceTwo;
      fin.close();

      cout<<"Opening Balance: $"<<OpenBalance;
      cout<<"\nDeposit: $"<<Deposit<<"       New Balance: $"<<NewBalance;
      cout<<"Withdrawal: $"<<Withdrawal<<"      New Balance: $"<<NewBalanceTwo;

      cin<<NewBalance;

      return 0;
}

and when you save to the file use this:

Code:

ofstream fout;
fout.open("bank.txt");
fout>>OpenBalance;
fout>>Deposit;
fout>>Withdrawal;
fout>>NewBalance;
fout>>NewBalanceTwo;
fout.close();

make sure your numbers are stored in the variables i used, or jsut switch my variable names to yours.

Thanks a lot all!