itextsharp 从 pdfwriter 更改为 pdfstamper 以保留 PDF 中的书签

itextsharp change from pdfwriter to pdfstamper to keep bookmarks in PDF

我正在使用 iTextSharp 将 PDF 文档合并在一起。我的问题是我正在尝试合并包含书签的大型 PDF。我当前的功能是使用 PdfWriter 合并文档。我知道 PdfStamper 可以工作,但我不知道如何更改该功能才能正常工作。

当我在下面的示例中将 PdfWriter 更改为 PdfStamper 时,出现错误。

代码示例:

writer = PdfStamper.GetInstance(pdfDoc, New FileStream(outputPath, FileMode.OpenOrCreate))

错误信息:

'GetInstance' is not a member of 'iTextSharp.text.pdf.PdfStamper'

这是整个函数:

Public Shared Function MergePdfFiles(ByVal pdfFiles() As String, ByVal outputPath As String) As Boolean
    Dim result As Boolean = False
    Dim pdfCount As Integer = 0     
    Dim f As Integer = 0    
    Dim fName As String
    Dim reader As iTextSharp.text.pdf.PdfReader = Nothing
    Dim pageCount As Integer = 0
    Dim pdfDoc As iTextSharp.text.Document = Nothing    
    Dim writer As PdfWriter = Nothing
    Dim cb As PdfContentByte = Nothing

    Dim page As PdfImportedPage = Nothing
    Dim rotation As Integer = 0

    Try
        pdfCount = pdfFiles.Length
        If pdfCount > 1 Then
            fName = pdfFiles(f)
            reader = New iTextSharp.text.pdf.PdfReader(fName)
            pageCount = reader.NumberOfPages

            pdfDoc = New iTextSharp.text.Document(reader.GetPageSizeWithRotation(1), 18, 18, 18, 18)

            writer = PdfWriter.GetInstance(pdfDoc, New FileStream(outputPath, FileMode.OpenOrCreate))

            With pdfDoc
                .Open()
            End With
            cb = writer.DirectContent
            While f < pdfCount
                Dim i As Integer = 0
                While i < pageCount
                    i += 1
                    pdfDoc.SetPageSize(reader.GetPageSizeWithRotation(i))
                    pdfDoc.NewPage()
                    page = writer.GetImportedPage(reader, i)
                    rotation = reader.GetPageRotation(i)
                    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
                End While
                f += 1
                If f < pdfCount Then
                    fName = pdfFiles(f)
                    reader = New iTextSharp.text.pdf.PdfReader(fName)
                    pageCount = reader.NumberOfPages
                End If
            End While
            pdfDoc.Close()
            result = True
        End If
    Catch ex As Exception
        MessageBox.Show(ex.Message)
        Return False
    End Try
    Return result
End Function

您不能只将 PdfWriter 更改为 PdfStamper。您需要创建一个带有 reader 和输出流的压模:

PdfReader reader = new PdfReader(pathToSrc);
PdfStamper.GetInstance(reader, New FileStream(outputPath, FileMode.OpenOrCreate));
// do stuff
stamper.Close();

如果您使用 PdfStamper,则不需要 Document 实例;你只需要更仔细地阅读文档。

上面这些对你都没用,因为PdfStamper是你操作单个文件时要用的class。如果你想合并不同的文件,你需要使用 PdfCopyPdfSmartCopy.

请查看 ConcatenateBookmarks 示例。如果您不理解,页面底部有一个 C# 示例 Java。

如果您还有其他问题,请浏览 iText 官方网站。