QT恢复上一次窗口退出状态，代码

Qt 记住上次打开路径

QFileDialog记录上次打开位置

QFileDialog记录上次打开位置

QFileDialog几个选择文件和文件夹的方法都有一个默认路径参数，如：

QString getExistingDirectory(QWidget *parent = nullptr, const QString &caption = QString(), const QString &dir = QString(), QFileDialog::Options options = ShowDirsOnly)

参数 const QString &dir = QString() 指定了打开的默认路径，只要将这个参数设置为空，那么QFileDialog就会自动定位到上次打开的路径。

QFileDialog::getExistingDirectory(this, tr("选择文件夹"), "", QFileDialog::ShowDirsOnly | QFileDialog::DontResolveSymlinks);

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原文链接：https://blog.csdn.net/wangw8507/article/details/116913574

Qt 记住上次打开路径

https://blog.csdn.net/artisans/article/details/44949645?utm_source=blogxgwz9

QT恢复上一次窗口退出状态，代码

https://blog.csdn.net/lzhangcheng/article/details/80339700

void MainWindow::readSetting ()
{
    QSettings settings("1321235", "123");

    QRect geom = this->rect();
    QPoint pos = settings.value("pos", QPoint(200, 200)).toPoint();
    
    QSize sz = settings.value("size", QSize(2 * geom.width() / 3, 2 * geom.height() / 3)).toSize();
    
    move(pos);
    resize(sz);  
}

void MainWindow::writSetting()
{
    QSettings settings("1321235", "123");
    
    settings.setValue("pos", pos());
    settings.setValue("size", size());
}

void MainWindow::closeEvent(QCloseEvent* event)
{
    writSetting();
}

void MainWindow::readSetting ()
{
    QSettings settings("1321235", "123");

    QRect geom = this->rect();
    QPoint pos = settings.value("pos", QPoint(200, 200)).toPoint();
    
    QSize sz = settings.value("size", QSize(2 * geom.width() / 3, 2 * geom.height() / 3)).toSize();
    
    move(pos);
    resize(sz);  
}


void MainWindow::writSetting()
{ 
    QSettings settings("1321235", "123");
    
    settings.setValue("pos", pos());
    settings.setValue("size", size());
}


void MainWindow::closeEvent(QCloseEvent* event)
{ 
    writSetting();
}

使用QSetting记录上次窗口退出大小位置，窗口关闭时执行writeSetting()函数，在界面构造函数里执行readSetting（）函数；