Creating/writing into a new file in Qt

I am trying to write into a file and if the file doesn't exist create it. I have searched on the internet and nothing worked for me.

My code looks currently like this:

QString filename="Data.txt";
QFile file( filename );
if ( file.open(QIODevice::ReadWrite) )
{
    QTextStream stream( &file );
    stream << "something" << endl;
}

If I create a text file called Data in the directory, it remains empty. If I don't create anything it doesn't create the file either. I don't know what to do with this, this isn't the first way in which I tried to create/write into a file and none of the ways worked.

Thanks for your answers.

Solution 1:

That is weird, everything looks fine, are you sure it does not work for you? Because this main surely works for me, so I would look somewhere else for the source of your problem.

#include <QFile>
#include <QTextStream>


int main()
{
    QString filename = "Data.txt";
    QFile file(filename);
    if (file.open(QIODevice::ReadWrite)) {
        QTextStream stream(&file);
        stream << "something" << endl;
    }
}

The code you provided is also almost the same as the one provided in detailed description of QTextStream so I am pretty sure, that the problem is elsewhere :)

Also note, that the file is not called Data but Data.txt and should be created/located in the directory from which the program was run (not necessarily the one where the executable is located).

Solution 2:

Are you sure you're in the right directory?
Opening a file without a full path will open it in the current working directory. In most cases this is not what you want. Try changing the first line to

QString filename="c:\\Data.txt" or
QString filename="c:/Data.txt"

and see if the file is created in c:\

Solution 3:

#include <QFile>
#include <QCoreApplication>
#include <QTextStream>

int main(int argc, char *argv[])
{
    // Create a new file     
    QFile file("out.txt");
    file.open(QIODevice::WriteOnly | QIODevice::Text);
    QTextStream out(&file);
    out << "This file is generated by Qt\n";

    // optional, as QFile destructor will already do it:
    file.close(); 

    //this would normally start the event loop, but is not needed for this
    //minimal example:
    //return app.exec();

    return 0;
}