Qt实现保存、浏览、预览、打印功能的示例代码

void MainWindow::on_btnSave_clicked()
{
 QString fileName = QFileDialog::getSaveFileName(this, tr("导出PDF文件"), QString(), "*.pdf");
 if (!fileName.isEmpty())
 {
 // 如果文件后缀为空，则默认使用.pdf
 if (QFileInfo(fileName).suffix().isEmpty())
 {
  fileName.append(".pdf");
 }
 QPrinter printer;
 // 指定输出格式为pdf
 printer.setOutputFormat(QPrinter::PdfFormat);
 printer.setOutputFileName(fileName);
 // ui->textEdit->print(&printer);
 ui->tableWidget->render(&printer);
 }
}

void MainWindow::on_btnSave_clicked()
{
 QString fileName = QFileDialog::getSaveFileName(this, tr("保存PDF文件"), QString(), "*.pdf");
 if (!fileName.isEmpty())
 {
 // 如果文件后缀为空，则默认使用.pdf
 if (QFileInfo(fileName).suffix().isEmpty())
 {
  fileName.append(".pdf");
 }
 QPrinter printerPixmap(QPrinter::HighResolution);
 //自定义纸张大小，这里要打印的内容都在stackedWidget上
 printerPixmap.setPageSize(QPrinter::Custom);
 printerPixmap.setPaperSize(QSizeF(ui->stackedWidget->height(), ui->stackedWidget->width()), QPrinter::Point);
 //设置纸张大小为A4，这里注释掉了，建议自定义纸张 ，否则保存的就会有很多空白
 //printerPixmap.setPageSize(QPrinter::A4);
 //横向打印
 printerPixmap.setOrientation(QPrinter::Landscape);
 //设置输出格式为pdf
 printerPixmap.setOutputFormat(QPrinter::PdfFormat);
 //设置输出路径
 printerPixmap.setOutputFileName(fileName);
 //获取界面的图片
 QPixmap pixmap = QPixmap::grabWidget(ui->stackedWidget, ui->stackedWidget->rect());
 QPainter painterPixmap;
 painterPixmap.begin(&printerPixmap);
 QRect rect = painterPixmap.viewport();
 int x = rect.width() / pixmap.width();
 int y = rect.height() / pixmap.height();
 //将图像(所有要画的东西)在pdf上按比例尺缩放
 painterPixmap.scale(x, y);
 //画图
 painterPixmap.drawPixmap(0, 0, pixmap);
 painterPixmap.end();
 QMessageBox::information(this, tr("生成PDF"), tr("保存PDF文件成功"), QMessageBox::Ok);
 }
}

QString fileName = QFileDialog::getOpenFileName(this, tr("选择文件"),QString(),
       tr("PDF 文档 (*.pdf);;所有文件 (*.*)"));
 QProcess * p = new QProcess;
 p->start("C:\\Program Files (x86)\\Foxit Software\\Foxit Reader Plus\\FoxitReaderPlus.exe",
  QStringList() << fileName);

void MainWindow::on_btnPreview_clicked()
{
 QPrinter printer(QPrinter::HighResolution);
 //自定义纸张大小
 printer.setPageSize(QPrinter::Custom);
 printer.setPaperSize(QSizeF(ui->stackedWidget->height(), ui->stackedWidget->width()),
    QPrinter::Point);
 QPrintPreviewDialog preview(&printer, this);
 preview.setMinimumSize(1000,600);
 connect(&preview, SIGNAL(paintRequested(QPrinter*)), SLOT(printPreviewSlot(QPrinter*)));
 preview.exec ();
}

void MainWindow::printPreviewSlot(QPrinter *printerPixmap)
{
 printerPixmap->setOrientation(QPrinter::Landscape);
 //获取界面的图片
 QPixmap pixmap = QPixmap::grabWidget(ui->stackedWidget, ui->stackedWidget->rect());
 QPainter painterPixmap(this);
 painterPixmap.begin(printerPixmap);
 QRect rect = painterPixmap.viewport();
 int x = rect.width() / pixmap.width();
 int y = rect.height() / pixmap.height();
 painterPixmap.scale(x, y);
 painterPixmap.drawPixmap(0, 0, pixmap);
 painterPixmap.end();
}

void MainWindow::on_btnPrint_clicked()
{
 // 创建打印机对象
 QPrinter printer;
 // 创建打印对话框
 QString printerName = printer.printerName();
 if( printerName.size() == 0)
 return;
 QPrintDialog dlg(&printer, this);
 //如果编辑器中有选中区域，则打印选中区域
 if (ui->textEdit->textCursor().hasSelection())
 dlg.addEnabledOption(QAbstractPrintDialog::PrintSelection);
 // 如果在对话框中按下了打印按钮，则执行打印操作
 if (dlg.exec() == QDialog::Accepted)
 {
 ui->textEdit->print(&printer);
 }
}

void MainWindow::on_btnPrint_2_clicked()
{
 QPrinter printerPixmap;
 QPixmap pixmap = QPixmap::grabWidget(ui->stackedWidget, ui->stackedWidget->rect()); //获取界面的图片
 QPrintDialog print(&printerPixmap, this);
 if (print.exec())
 {
 QPainter painterPixmap;
 painterPixmap.begin(&printerPixmap);
 QRect rect = painterPixmap.viewport();
 int x = rect.width() / pixmap.width();
 int y = rect.height() / pixmap.height();
 painterPixmap.scale(x, y); 
 painterPixmap.drawPixmap(0, 0, pixmap); 
 painterPixmap.end();
 }
}