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hot to change int to the string type

  • Hi, i'm using qt5.5 on my computer.
    I have a program like below.

    void MainWindow::on_horizontalSlider_volume_valueChanged(int value)
        QString info;
        Process::executeProcessSync(QString("sh"),QStringList()<<"-c"<<"/usr/bin/amixer set Speaker "+value+"%",&info);

    But it will show the error for me when i compile, it's the content of the error.

    mainwindow.cpp:2697:105: error: invalid operands of types 'const char*' and 'const char [2]' to binary 'operator+'
         Process::executeProcessSync(QString("sh"),QStringList()<<"-c"<<"/usr/bin/amixer set Speaker "+value+"%",&info);

    How can i fix the problem?
    I don't know where did i do wrong?
    Please help!

  • Moderators

    @victor-wang To convert an Interger into a String is kind of the part basics of the c++/qt libary. Did you look herebefore posting?

    Anyway, you can either use arg
    or the static QString::Number

  • Qt Champions 2018

    @J-Hilk is correct but in this specific case I would not use arg() because it localises the string (i.e. it might put in thousands separators and use local decimal separators)

  • try:
    QStringList() << "-c" << "/usr/bin/amixer set Speaker " + QString::number(value) + "%"

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