1.获取多个文件路径+名字

    #include <QFileDialog>
    void MainWindow::on_pushButton_clicked()
    {
        QString dialog[3],name[4];
        QStringList split[3];
        QFileDialog add_file_dialog;
        add_file_dialog.setFileMode(QFileDialog::ExistingFiles);
        QStringList filename=add_file_dialog.getOpenFileNames(
                    this, tr("open txt"),".", tr("select(*.txt)"));
        int i=0;
        for(auto temp:filename){
            dialog[i]=temp;
            split[i] = dialog[i].split("/");
            name[i] = split[i].last();
            i++;
        }
        name[3] = QString("%1,%2,%3").arg(name[0]).arg(name[1]).arg(name[2]);
        ui->label->setText(name[3]);
    }

2.获取路径+新建名字

QString saveName;//保存名字
QString savePath;
QString filePath;//存储保存路径
QDateTime time = QDateTime::currentDateTime();//获取系统现在的时间
QString str = time.toString("mm:ss-yyyyMMdd"); //设置显示格式
filePath = QFileDialog::getExistingDirectory(this,"");//获取文件夹路径
if(!filePath.isEmpty())
{
    saveName="savename";
    savePath=QString("%1/%2-%3.txt").arg(filePath).arg(saveName).arg(str);
    const std::string save = savePath.toStdString();
    //todo
}

3.覆盖写入

    std::ofstream outFile(savePath);//example:string savePath = "/a.txt"
    for(int i=0;i<10;i++){outFile<<i<<" ";}
    outFile.close();

3.读入

std::ifstream inFile(savePath);
if(inFile){
        for(int i=0;i<8;i++){inFile>>parameter[i];}
        inFile.close();
    }