Qfile22

#include <QCoreApplication>

#include <QFile>

#include <QTextStream>

int main(int argc, char *argv[])

{

    QCoreApplication a(argc, argv);

    QFile data("QFile.txt");

    if(data.open(QFile::WriteOnly|QFile::Truncate))

    {

        QTextStream out(&data);

        out<<QObject::tr("aaa:")<<qSetFieldWidth(10)<<left<<90<<endl;

    }

    return a.exec();

}

QFile data("QFile.txt");

data.open(QFile::WriteOnly|QFile::Truncate)

 QTextStream out(&data);

binary:

void MainWindow::fileFun()

{

    QFile file("binary.dat");

    file.open(QIODevice::WriteOnly | QIODevice::Truncate);

    QDataStream out(&file);                             //将数据序列化

    out << QString(tr("this_is_a_tiger:"));                      //字符串序列化

    out << QDate::fromString("2020/09/25", "yyyy/MM/dd");

    out << (qint32)19;                                 	//整数序列化

    file.close();

    file.setFileName("binary.dat");

    if(!file.open(QIODevice::ReadOnly))

    {

         qDebug()<< "error!";

         return;

    }

    QDataStream in(&file);                            	//从文件中读出数据

    QString name;

    QDate birthday;

    qint32 age;

    in >> name >> birthday >> age;                    	//获取字符串和整数

    qDebug() << name << birthday << age;

    file.close();

}

 QFile file("binary.dat");

file.open(QIODevice::WriteOnly | QIODevice::Truncate);

 QDataStream out(&file);

 file.close();