将文档导出为pdf

#include <QtWidgets>
/* 需要为项目文件添加QT += printsupport */
#include <QPrinter> 

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

    QPrinter printer(QPrinter::PrinterResolution);
    printer.setOutputFormat(QPrinter::PdfFormat);
    printer.setPaperSize(QPrinter::A4);
    printer.setOutputFileName("hello.pdf");

    QTextDocument doc;
    doc.setPlainText("Hello world!"); /* 可替换为文档内容 */
    doc.setPageSize(printer.pageRect().size());
    doc.print(&printer);
}