PDF填写未正确合并

Question

我们正在使用带有iTextSharp.dll 5.5.13版的asp.net网站。我们可以使用流将多个PDF文件合并为一个文件，并且效果很好。但是，当我们使用在“填充”功能中创建的PDF时，新的PDF文件无法正确合并到其他文档中。它合并而没有填充值。但是，如果我打开填充的PDF，它将创建填充的数据显示并可以正常打印。

我稍后尝试合并新的“填充” PDF，但是它仍然显示模板文件，好像丢失了填充数据。

以下代码填写数据

Dim strFileName As String = Path.GetFileNameWithoutExtension(strSourceFile)
Dim strOutPath As String = HttpContext.Current.Server.MapPath("~/Apps/Lifetime/OfficeDocs/Export/")
newFile = strOutPath & strFileName & " " & strRONumber & ".pdf"

If Not File.Exists(newFile) Then
    Dim pdfReader As PdfReader = New PdfReader(strSourceFile)
    Using pdfStamper As PdfStamper = New PdfStamper(pdfReader, New FileStream(newFile, FileMode.Create))

        Dim pdfFormFields As AcroFields = pdfStamper.AcroFields
        pdfFormFields.SetField("CUSTOMER NAME", strCustomer)
        pdfFormFields.SetField("YR MK MODEL", strVehicle)
        pdfFormFields.SetField("RO#", strRONumber)

        pdfStamper.FormFlattening = False
        pdfStamper.Dispose()
    End Using

End If

然后下面的代码将合并发送给它的多个PDF文件/路径

Public Shared Sub MergePDFs(ByVal files As List(Of String), ByVal filename As String)
    'Gets a list of full path files and merges into one memory stream
    'and outputs it to a browser response.
    Dim MemStream As New System.IO.MemoryStream
    Dim doc As New iTextSharp.text.Document
    Dim reader As iTextSharp.text.pdf.PdfReader
    Dim numberOfPages As Integer
    Dim currentPageNumber As Integer
    Dim writer As iTextSharp.text.pdf.PdfWriter = iTextSharp.text.pdf.PdfWriter.GetInstance(doc, MemStream)
    doc.Open()
    Dim cb As iTextSharp.text.pdf.PdfContentByte = writer.DirectContent
    Dim page As iTextSharp.text.pdf.PdfImportedPage
    Dim strError As String = ""

    For Each strfile As String In files
        reader = New iTextSharp.text.pdf.PdfReader(strfile)
        numberOfPages = reader.NumberOfPages
        currentPageNumber = 0
        Do While (currentPageNumber < numberOfPages)
            currentPageNumber += 1
            doc.SetPageSize(reader.GetPageSizeWithRotation(currentPageNumber))
            doc.NewPage()
            page = writer.GetImportedPage(reader, currentPageNumber)
            cb.AddTemplate(page, 0, 0)
        Loop
    Next
    doc.Close()
    doc.Dispose()

    If MemStream Is Nothing Then
        HttpContext.Current.Response.Write("No Data is available for output")
    Else
        HttpContext.Current.Response.Clear()
        HttpContext.Current.Response.ContentType = "application/pdf"
        HttpContext.Current.Response.AppendHeader("Content-Disposition", "inline; filename=" + filename)
        HttpContext.Current.Response.BinaryWrite(MemStream.ToArray)
        HttpContext.Current.Response.OutputStream.Flush()
        HttpContext.Current.Response.OutputStream.Close()
        HttpContext.Current.Response.OutputStream.Dispose()
        MemStream.Close()
        MemStream.Dispose()
    End If
End Sub

我希望文件列表中的“已填充” PDF保留已填充数据，但不会。即使我稍后尝试合并填充的文件，它仍然会丢失填充的数据。如果我打印填写的文件，它看起来很完美。

Answer 1

not不包含任何注释，特别是不包含当前页面上表单字段的窗口小部件注释。

要复制源页面的注释，请改用iText PdfCopy类。此类旨在复制包括所有注释的页面。此外，它还包括一步复制源文档所有页面的方法。

您必须告诉PdfCopy对象合并字段，否则将不会构建

文档范围

表单结构。

顺便说一句，您的代码创建了许多PdfReader对象，但没有关闭它们。这可能会大大增加您的内存需求。

因此：

Public Shared Sub MergePDFsImproved(ByVal files As List(Of String), ByVal filename As String)
    Using mem As New MemoryStream()
        Dim readers As New List(Of PdfReader)
        Using doc As New Document
            Dim copy As New PdfCopy(doc, mem)
            copy.SetMergeFields()
            doc.Open()
            For Each strfile As String In files
                Dim reader As New PdfReader(strfile)
                copy.AddDocument(reader)
                readers.Add(reader)
            Next
        End Using
        For Each reader As PdfReader In readers
            reader.Close()
        Next

        HttpContext.Current.Response.Clear()
        HttpContext.Current.Response.ContentType = "application/pdf"
        HttpContext.Current.Response.AppendHeader("Content-Disposition", "inline; filename=" + filename)
        HttpContext.Current.Response.BinaryWrite(mem.ToArray)
        HttpContext.Current.Response.OutputStream.Flush()
        HttpContext.Current.Response.OutputStream.Close()
        HttpContext.Current.Response.OutputStream.Dispose()
    End Using
End Sub

实际上，我不确定Close和Dispose这里的响应输出流是否是一个好主意，这不应该是PDF合并方法的责任。

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