Thread: i need your help about writing data to file

Code:

#include <iostream>
#include <bitset>

using namespace std;

int main()
{
	// 16 bits each
	short num;
	
	// file to be written
	ofstream file_in("file");

	// 15 is equal to 000...01111
	num = 15;
	file_in << num;
	file_in.close();
	
	// reseting, not necessary, but to make sure it works
	num = 0;

	// Lets just read 15 again
  ifstream file_out("file");
  file_out >> num;
  
	cout << "The number is " << num << endl;
	cin.get();

  return 0;
}

Hope that helps... also, have a look at bitset class, it might be useful.

but all you need to do to use binary
i believe is open the file in binary,

The issue is how to write bits when all you can work with are bytes.

john_tran:
You must arrange the bits 8 at a time, into a byte. If you want to write 10010, then 00010, you have to somehow make it into 10010000 and 10000000 instead (I put extra 0's after the 10 so that it would be 8 bits in total). Then you can write them one at a time to the file.