Question

I have a problem, I have a saved text file, I want to use fstream header file in C++ to write something to that file, but using ofstream will erase the whole file as soon as I run the compiled application, why and how to avoid it?

#include <fstream>
#include <iostream>
using namespace std;

int main()
{
    ofstream write("1.txt");
    return 0;
}

Answer 1

You need to tell ofstream to append to the file.

std::ofstream write("1.txt",std::ios::app);

There are several other flags that control similar characteristics of the stream, read a book or reference for more information.