iTextSharp - 如何在 C# winforms 中并排迭代表格？

Question

我有一个图书馆，我想为他们打印图书馆标签。当您从 GridControl 中选择书籍并单击 Print Labels 按钮时，程序会在 pdf 文件上创建标签，如下所示：

private void btnQRPrintLabels_Click(object sender, EventArgs e)
{
    // These are books' ids. Normally, these are retrieved from GridControl element.
    var books_ids = new List<int>() {1, 2, 5, 6, 7, 12};
    // I don't use PanelControl. But in the future, maybe I can use it later.
    CreateLabels(books_ids, panelControl1);
}

这里是CreateLabels方法的内容：

public void CreateLabels(List<int> books_ids, PanelControl p)
{
    var doc = new Document(PageSize.A4, 10, 10, 10, 10);
    var m = new SaveFileDialog
    {
        Filter = @"PDF File Format|*.pdf",
        FileName = "Labels.pdf"
    };

    if (m.ShowDialog() != DialogResult.OK) return;

    var file = new FileStream(m.FileName, FileMode.Create);
    wr = PdfWriter.GetInstance(doc, file);

    doc.Open();
    cb = wr.DirectContent;
    wr.PageEvent = this;
    // Labels are created from this method.
    Labels(doc, books_ids);
    doc.Close();
}

最后是Labels方法的内容：

protected void Labels(Document doc, List<int> books_ids)
{
    var i = 1;
    foreach (var book_id in books_ids)
    {
        var alignment = (i % 2 != 0) ? Element.ALIGN_LEFT : Element.ALIGN_RIGHT;

        // Book's informations are retrieved from Linq Connect Model.
        var _connection = new LinqtoSQLiteDataContext();
        var book = _connection.books.SingleOrDefault(b_no => b_no.id == book_id);
        // Outer table to get rounded corner...
        var table = new PdfPTable(1) { WidthPercentage = 48, HorizontalAlignment = alignment };
        // Inner table: First cell for QR code and second cell for book's informations.
        var inner_table = new PdfPTable(2) { WidthPercentage = 100 };
        inner_table.DefaultCell.Border = Rectangle.NO_BORDER;

        var inner_measurements = new[] { 40f, 60f };
        inner_table.SetWidths(inner_measurements);
        // Generate QR code in the `Tools` class, `GenerateQR` method.
        System.Drawing.Image image = Tools.GenerateQR(100, 100, book?.isbn);
        var pdfImage = iTextSharp.text.Image.GetInstance(image, System.Drawing.Imaging.ImageFormat.Jpeg);
        var qr = iTextSharp.text.Image.GetInstance(pdfImage);

        var a = new PdfPCell(qr) { Border = Rectangle.NO_BORDER };
        var b = new PdfPCell(new Phrase(book?.name, font_normal)) { Border = Rectangle.NO_BORDER };

        inner_table.AddCell(a);
        inner_table.AddCell(b);

        var s = new PdfPCell(inner_table)
        {
            CellEvent = new RoundRectangle(),
            Border = Rectangle.NO_BORDER,
            Padding = 2,
            HorizontalAlignment = Element.ALIGN_LEFT
        };
        table.AddCell(s);
        doc.Add(table);
        i++;
    }
}

这些代码给我带来这样的标签：

但我想得到这样的标签：

因为如果我设法并排获取标签，我可以轻松地将其打印到计算机标签上。这是我想在上面打印的计算机标签：

如何并排迭代表？

Answer 1

使用一个外部表与

new PdfPTable(2) { WidthPercentage = 100 }

然后将所有内部表添加到此表中，最后将外部表添加到文档中。这样就不需要使用切换左/右对齐方式了。

：编辑：

var table = new PdfPTable(2) { WidthPercentage = 100 };

foreach (var book_id in books_ids)
{
  // Book's informations are retrieved from Linq Connect Model.
  var _connection = new LinqtoSQLiteDataContext();
  var book = _connection.books.SingleOrDefault(b_no => b_no.id == book_id);
  // Outer table to get rounded corner...

  // Inner table: First cell for QR code and second cell for book's informations.
  var inner_table = new PdfPTable(2) { WidthPercentage = 100 };
  inner_table.DefaultCell.Border = Rectangle.NO_BORDER;

  var inner_measurements = new[] { 40f, 60f };
  inner_table.SetWidths(inner_measurements);
  // Generate QR code in the `Tools` class, `GenerateQR` method.
  System.Drawing.Image image = Tools.GenerateQR(100, 100, book?.isbn);
  var pdfImage = iTextSharp.text.Image.GetInstance(image, System.Drawing.Imaging.ImageFormat.Jpeg);
  var qr = iTextSharp.text.Image.GetInstance(pdfImage);

  var a = new PdfPCell(qr) { Border = Rectangle.NO_BORDER };
  var b = new PdfPCell(new Phrase(book?.name, font_normal)) { Border = Rectangle.NO_BORDER };

  inner_table.AddCell(a);
  inner_table.AddCell(b);

  PdfPCell labelCell = new PdfPCell(inner_table)
  {
      CellEvent = new RoundRectangle(),
      Border = Rectangle.NO_BORDER,
      Padding = 2,
      HorizontalAlignment = Element.ALIGN_LEFT
  };

  table.AddCell(labelCell);               
}

doc.Add(table);

Answer 2

只需添加页面级表格（2 列，6 行）并将每个标签放入此页面级表格的单个单元格中。