How do i write in my txt file and append text below

Question

I cant seem to have output appears in my .txt file. I would like to append below the text file in future.

using namespace std;

int main()
{
    string month;
    int year;
    stringstream filename;

    cin >> month;
    cin >> year;

    filename << "Expenses_" << month << "_" << year << ".txt";
    ofstream myfile(filename.str()); 

    myfile.open(filename.str());
    myfile << "Hello World!";
    myfile.close();

    return 0;
}

[Any good beginners book](http://stackoverflow.com/questions/388242/the-definitive-c-book-guide-and-list) should have information about it. [A good reference of the C++ input/output system](http://en.cppreference.com/w/cpp/io) should also be helpful. — Some programmer dude, Nov 17 '17 at 08:01

score 0 · Answer 1 · answered Nov 17 '17 at 08:01

0

Open your file as:

std::ofstream myfile(filename.str(), std::ofstream::out | std::ofstream::app);

And passing the filename while creating the object of ofstream will open that file too, you don't need to call .open again.

answered Nov 17 '17 at 08:01

Ahmad Khan

2,655
19
25

score 0 · Answer 2 · answered Nov 17 '17 at 09:17

ofstream myfile(filename.str(), ofstream::out | ofstream::app);

The constructor automatically opens the file for writing and moves the writing pointer to the end of the file, so you can append to the file. There's no need to open the file again because the std::ofstream(const char*, int) consturctor has already opened the file for you.

The alternative is:

ofstream myfile;
myfile.open(filename.str(), ofstream::out | ofstream::app);

How do i write in my txt file and append text below

2 Answers2