Search code examples
c++qtqstringqtcoreqsettings

QSettings::IniFormat values with "," returned as QStringList


I am using QSettings to parse an ini file: QSettings cfg(path, QSettings::IniFormat);

When I obtain a value QVariant qv = cfg.value("title"); containing a comma the variant contains a QStringList instead of a QString

title=foo => QString
title=foo,bar => QStringList

How can I always get strings, or at least obtain the original line ( title=foo,bar ) ?


Solution

  • You have at least two ways to address this issue, all of them presented below:

    test.ini

    title="foo,bar"
    title_unquoted=foo,bar
    

    main.cpp

    #include <QSettings>
    #include <QDebug>
    
    int main()
    {
        QSettings settings("test.ini", QSettings::IniFormat);
        // Original issue
        qDebug() << settings.value("title_unquoted");
        // 1st solution: join the strings
        qDebug() << settings.value("title").toStringList().join(',');
        // 2nd solution: use quotes in the ini file
        qDebug() << settings.value("title");
        return 0;
    }
    

    main.pro

    TEMPLATE = app
    TARGET = main
    QT = core
    SOURCES += main.cpp
    

    Build and Run

    qmake && make && ./main
    

    Output

    QVariant(QStringList, ("foo", "bar"))
    "foo,bar"
    QVariant(QString, "foo,bar")
    

    In other words, use quotes for strings with special characters or join the strings manually in the list. The former is far better if it is under your control as you usually ought to aim for proper quoting when using "special" characters in strings.