如何用QT实现文件的读写

    读文件
    QFile file_r("/home/xmltest/data.txt");
    if (!file_r.open(QIODevice::ReadOnly | QIODevice::Text))
    {
        qDebug("fail");
    }
    while (!file_r.atEnd())
    {
        QByteArray line = file_r.readLine();
        qDebug()<<line;
        readDate.append(QString(line));
        listWidget->addItem(readDate.value(1));
    }
    file_r.close();

    写文件
    QStringList dateList;
    dateList<<"gfsdj"
            <<"sghfjs"
            <<"s2222";
    qDebug()<<dateList;

    QFile file_w("/home/xmltest/data.txt");
    if(!file_w.open(QIODevice::Append | QIODevice::Text))
    {
        qDebug("fail");
    }
    QTextStream tt(&file_w);
    for(int i=0;i<3;i++)
    {
        tt<<dateList.value(i)<<endl;
    }
    file_w.close();

------解决方案--------------------

C/C++ code

     QFile file("in.txt");
     if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
         return;

     QTextStream in(&file);
     while (!in.atEnd()) {
         QString line = in.readLine();
         process_line(line);
     }

     QFile file("out.txt");
     if (!file.open(QIODevice::WriteOnly | QIODevice::Text))
         return;

     QTextStream out(&file);
     out << "The magic number is: " << 49 << "\n";