Write data in TXT

AlvaroS

Hello everyone.
First of all thanks for helping me and reading this post.

I would like to write a std::map data in a .TXT.

I write this code:

void MainWindow::on_Save_TXT_button_clicked()
{
    QString file_save = QFileDialog::getSaveFileName(this, "Guardar TXT", "/home", "files TXT (*.txt)");

        if(!file_save.isEmpty()) //If the user have choosen a file then:
        {
            QFile file_s(file_save); //The QFile class can read and write files. Here we do that namefile will be QFile type with name file.


            if(file_s.open(QFile::WriteOnly))
            {   
            fopen(file_save,"w");
            fprintf(....)
            fclose(...)
            //TODO SAVE THE DATA MAP
            }
        }
}

With that, the user can specify the file name and path.
But the problem appears when I use fopen because file_save is not a FILE it is a QString.
So how can I use that with fopen, fprinf and fclose?

Thanks a lot.

mrjj

Hi
Why try to mix QFile and old c, fopen fwrite etc?
You can do it all with Qt classes

#include <QString>
#include <QFile>
#include <QDebug>
#include <QTextStream>

int main(int argc, char **argv)
{
    /* Try and open a file for output */
    QString outputFilename = "Results.txt";
    QFile outputFile(outputFilename);
    outputFile.open(QIODevice::WriteOnly);

    /* Check it opened OK */
    if(!outputFile.isOpen()){
        qDebug() << argv[0] << "- Error, unable to open" << outputFilename << "for output";
        return 1;
    }

    /* Point a QTextStream object at the file */
    QTextStream outStream(&outputFile);

    /* Write the line to the file */
    outStream << "Victory!\n";
// u write ur members of the map.

    /* Close the file */
    outputFile.close();
    return 0;
}

AlvaroS

@mrjj Thanks a lot my friend.
But how can I acces to spaces and \n in QTextStream?
Because I need a \n in each line.

so like this:
line1
line2
line3
.
.
.

maybe with void QTextStream::setFieldWidth(int width)?

Thanks a lot again.

mrjj

@AlvaroS

outStream << "line1" << "\n" << "line2" << "\n";

and space is just " ".

Or do I misunderstand what you ask?

AlvaroS

@mrjj Thanks a lot my friend. It works really fine!!!!!!!!

mrjj

@AlvaroS
Super :)
The best benefit of using a QTextStream is that
most of Qt classes have overload the << so they can just be saved.

Note: Be careful with pointers
QWidget *w;

stream << w; will write the address
stream << *w; will write the object (if object have << defined)

AlvaroS

@mrjj Yes!!! I was careful with that and It worked really fine! Thanks again!