How do I add table to existing pdf using iTextSharp

问题

I'm developing an app to merging pdf documents into one document using itextsharp. I've gotten the single pdf created.

Now I have to create a table and add it to the first page.

Unfortunately this is becoming more complicated than it seams. After hours of trying I was able to add the table into the second page.

How can I add the table to the first page?

I'm using this sample project for testing http://gamepacks.org/Sample.zip.

Public Sub MergePdfFiles(ByVal docList As List(Of String), ByVal outputPath As String)

    Try
        '
        ' http://www.vbforums.com/showthread.php?475920-Merge-Pdf-Files-and-Add-Bookmarks-to-It-(Using-iTextSharp)
        '
        If docList.Count = 0 Then Exit Sub

        Dim OutlineList As List(Of PdfOutline) = New List(Of PdfOutline)
        Dim FirstPageIndex As Integer = 1           ' Tracks which page to link the bookmark

        Dim result As Boolean = False
        Dim pdfCount As Integer = 0             'total input pdf file count

        Dim fileName As String = String.Empty           'current input pdf filename

        Dim reader As iTextSharp.text.pdf.PdfReader = Nothing
        Dim pageCount As Integer = 0                'current input pdf page count
        Dim doc As iTextSharp.text.Document = Nothing       'the output pdf document
        Dim writer As PdfWriter = Nothing
        Dim cb As PdfContentByte = Nothing

        'Declare a variable to hold the imported pages
        Dim page As PdfImportedPage = Nothing
        Dim rotation As Integer = 0

        'Now loop thru the input pdfs
        For Each row As String In docList
            reader = New iTextSharp.text.pdf.PdfReader(row)

            ' Is this the first pdf file
            If (row = docList(0)) Then
                doc = New iTextSharp.text.Document(reader.GetPageSizeWithRotation(1), 18, 18, 18, 18)
                writer = PdfWriter.GetInstance(doc, New IO.FileStream(outputPath, IO.FileMode.Create))
                doc.Open()
                ' Always show the bookmarks
                writer.ViewerPreferences = PdfWriter.PageModeUseOutlines

                'Instantiate a PdfContentByte object
                cb = writer.DirectContentUnder
            End If

            For i As Integer = 1 To reader.NumberOfPages
                'Get the input page size
                doc.SetPageSize(reader.GetPageSizeWithRotation(i))

                'Create a new page on the output document
                doc.NewPage()

                'Now we get the imported page
                page = writer.GetImportedPage(reader, i)

                'Read the imported page's rotation
                rotation = reader.GetPageRotation(i)

                'Then add the imported page to the PdfContentByte object as a template based on the page's rotation
                If rotation = 90 Then
                    cb.AddTemplate(page, 0, -1.0F, 1.0F, 0, 0, reader.GetPageSizeWithRotation(i).Height)
                ElseIf rotation = 270 Then
                    cb.AddTemplate(page, 0, 1.0F, -1.0F, 0, reader.GetPageSizeWithRotation(i).Width + 60, -30)
                Else
                    cb.AddTemplate(page, 1.0F, 0, 0, 1.0F, 0, 0)
                End If
            Next
        Next


        ' NEED TO ADD THIS TO THE FIRST PAGE
        doc.Add(_stateTable)




        doc.Close()
    Catch ex As Exception
        MessageBox.Show(ex.Message)
    End Try

End Sub




Private Function _stateTable() As PdfPTable
    Dim col As String() = {"No.", "Name", "City"}
    Dim table As New PdfPTable(3)

    table.WidthPercentage = 75
    table.SetWidths(New [Single]() {1, 5, 4})
    table.SpacingBefore = 10

    For i As Integer = 0 To col.Length - 1
        Dim cell As New PdfPCell(New Phrase(col(i)))
        cell.BackgroundColor = New BaseColor(204, 204, 204)
        table.AddCell(cell)
    Next

    table.AddCell("32")
    table.AddCell("Jack")
    table.AddCell("Sgeg")
    table.AddCell("33")
    table.AddCell("Mike")
    table.AddCell("Twin")

    Return table
End Function

回答1:

I don't know where you found the inspiration for writing your code, but I'm sorry to say that you've read the wrong documentation. When you copy a document using PdfWriter/PdfImportedPage, you're throwing away all interactivity that exists in the original document. Manipulating an existing page is done with PdfStamper as described in chapter 6 of my book. See table 6.1: http://www.manning.com/lowagie2/samplechapter6.pdf

If you want to stamp content on the first page, you need to use stamper.GetOverContent(1). See for instance this StampText example. Adding a table should be done with the WriteSelectedRows method, see for instance the PdfCalendar example.

Note that you need to define the coordinates of the table. Also understand that PDF is NOT a Word processing format. The table will overlap with any content that already exists at the coordinates you specified (because that's the way PDF works: all content is defined at absolute positions).

来源：https://stackoverflow.com/questions/14168110/how-do-i-add-table-to-existing-pdf-using-itextsharp