how to Load the PDF into a QPixmap c++-QT开发中文网

To load a PDF into a QPixmap in C++, you can use the Poppler library (which is already installed if you followed the previous answer). Here’s an example code:

#include <QApplication>
#include <QLabel>
#include <poppler-qt5.h>

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);

    // Load PDF document
    Poppler::Document* doc = Poppler::Document::load("path/to/your/pdf/file.pdf");
    if (!doc || doc->isLocked()) {
        qDebug() << "Error loading PDF";
        return 1;
    }

    // Get first page of the document
    Poppler::Page* page = doc->page(0);
    if (!page) {
        qDebug() << "Error getting page";
        delete doc;
        return 1;
    }

    // Render page to image
    QImage image = page->renderToImage();

    // Convert QImage to QPixmap and display it in a QLabel
    QPixmap pixmap = QPixmap::fromImage(image);
    QLabel label;
    label.setPixmap(pixmap);
    label.show();

    // Clean up resources
    delete page;
    delete doc;

    return app.exec();
}

In this example, we first load a PDF document using Poppler::Document::load() method. Then we get the first page of the document using Poppler::Document::page() method. We render this page to an image using Poppler::Page::renderToImage() method. Finally, we convert this QImage to a QPixmap and display it in a QLabel.

Note that you need to link your project with the Poppler library by adding LIBS += -lpoppler-qt5 to your .pro file.