Qt实现窗口截图功能

QScreen *screen=QGuiApplication::primaryScreen();
QPixmap pixmap=screen->grabWindow(ui->widget->winId());//ui->widget->winId()你需要截图的窗口id
pixmap.save("./1.jpg","jpg");

  QScreen *screen = QGuiApplication::primaryScreen();
    if (screen) {
        // 截取整个屏幕
        QPixmap screenshot = screen->grabWindow(0);


        // 可选择保存路径和文件名
        QString fileName = QFileDialog::getSaveFileName(nullptr, "保存截图",
                                                        QDateTime::currentDateTime().toString("yyyyMMdd_hhmmss") + ".png",
                                                        "Images (*.png *.xpm *.jpg)");


        if (!fileName.isEmpty()) {
            // 保存截图
            screenshot.save(fileName);
        }
    }

 QScreen *screen = QGuiApplication::primaryScreen();
    if (screen) {
        // 截取整个屏幕
        QPixmap screenshot = screen->grabWindow(0);


        // 创建 QPainter 对象在截图上绘制
        QPainter painter(&screenshot);


        // 设置水印样式
        painter.setPen(QColor(255, 0, 0, 128)); // 红色，透明度为128
        painter.setFont(QFont("Arial", 30, QFont::Bold));


        // 添加水印文本
        QString watermarkText = "小gpt";
        painter.drawText(screenshot.rect(), Qt::AlignVCenter | Qt::AlignHCenter, watermarkText);


        // 结束绘制
        painter.end();


        // 可选择保存路径和文件名
        QString fileName = QFileDialog::getSaveFileName(nullptr, "保存截图",
                                                        QDateTime::currentDateTime().toString("yyyyMMdd_hhmmss") + ".png",
                                                        "Images (*.png *.xpm *.jpg)");


        if (!fileName.isEmpty()) {
            // 保存带水印的截图
            screenshot.save(fileName);
        }
    }