将 iTextSharp PDF 作为内存流返回导致 StreamNotSupported

我正在 iTextSharp 中使用 PdfStamper 创建一个 PDF 文件，并将 PDF 作为内存流返回调用函数的对象，然后用于在 WinForms 的 Teleriks PDF 查看器组件中显示 PDF.

I'm creating a PDF file using the PdfStamper in iTextSharp and return the PDF as a memorystream object to the calling function, that is then used to display the PDF in Teleriks PDF Viewer Component for WinForms.

这就是目标.

现在，创建 PDF 正常工作，并将数据返回给 Calling 函数，在 Calling 函数中，我应该将内存流内容写入文件流，然后在 Adob​​e Reader 中打开它吗?很好.

Right now, creating the PDF works as it should, and it returns the data to the Calling function, and in the Calling function, should I write the memorystream contents to a file stream and then open it in Adobe Reader Everything looks just fine.

但是，如果我选择在 PDF 查看器控件中显示 PDF，我只会收到不支持的流类型"错误.

However, if I choose to display the PDF in the PDF Viewer Control I just get an "Unsupported Stream type" error.

现在，我发现 PDF 数据有问题，所以我决定创建 PDF 文件，将其保存到磁盘，然后在调用函数中将其读取到内存流并在 PDF 查看器中显示该内存流，对于一些对我来说未知的原因，有效......

Now, I figured something was wrong in the PDF data so I decided to create the PDF file, save it to disk, then read it to a memorystream in the Calling function and display that memorystream in the PDF Viewer and that, for some to me unknown reason, works....

我真的无法解决这个问题，需要一些帮助.

I really can't get my head around this and need some help.

所以，这行不通:

//The Calling function
private void dlgViewPDF_Load(object sender, EventArgs e)
{
    MemoryStream ms = PDFcreator.GeneratePDFdata(id);

   rPdfView.LoadDocument(ms);
}

//The PDF generator
public static MemoryStream GeneratePDFdata(string id)
{
    MemoryStream ms = new MemoryStream();

    string sTemplate = string.Concat(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location), "\template.pdf");

    PdfReader pdfReader = new PdfReader(sTemplate);
    PdfStamper pdfStamper = new PdfStamper(pdfReader, ms);

    PdfContentByte cb = pdfStamper.GetOverContent(1);

    BaseFont baseFont = BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.CP1250, BaseFont.EMBEDDED);
    BaseFont baseFontBold = BaseFont.CreateFont(BaseFont.HELVETICA_BOLD, BaseFont.CP1250, BaseFont.EMBEDDED);
    cb.SetColorFill(iTextSharp.text.Color.BLACK);
    cb.SetFontAndSize(baseFontBold, 14);

    cb.BeginText();
    cb.ShowTextAligned(PdfContentByte.ALIGN_LEFT, "TEST!!", 385, 750, 0);
    cb.EndText();

    cb.SetColorStroke(new CMYKColor(0f, 0f, 0f, 1f));
    cb.SetColorFill(new CMYKColor(0f, 0f, 0f, 1f));

    cb.MoveTo(139, 398);
    cb.LineTo(146, 398);
    cb.LineTo(146, 391);
    cb.LineTo(139, 391);
    cb.ClosePathEoFillStroke();

    pdfStamper.Close();
    pdfReader.Close();

    return ms;
}

但是出于某种原因，这确实有效:

However THIS does work for some reason:

//The Calling function
private void dlgViewPDF_Load(object sender, EventArgs e)
{
    MemoryStream ms = new MemoryStream();

    FileStream file = new FileStream(@"c:	emp	estfile.pdf", FileMode.Open, FileAccess.Read);

    byte[] bytes = new byte[file.Length];
    file.Read(bytes, 0, (int)file.Length);
    ms.Write(bytes, 0, (int)file.Length);

    rPdfView.LoadDocument(ms);
}


//The PDF generator 
public static void GeneratePDFdata(string id)
{
    MemoryStream ms = new MemoryStream();

    string sTemplate = string.Concat(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location), "\template.pdf");

    PdfReader pdfReader = new PdfReader(sTemplate);

    FileStream fs = new FileStream(@"c:	emp	estfile.pdf", FileMode.Create, FileAccess.Write, FileShare.None);
    PdfStamper pdfStamper = new PdfStamper(pdfReader, fs);

    PdfContentByte cb = pdfStamper.GetOverContent(1);

    BaseFont baseFont = BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.CP1250, BaseFont.EMBEDDED);
    BaseFont baseFontBold = BaseFont.CreateFont(BaseFont.HELVETICA_BOLD, BaseFont.CP1250, BaseFont.EMBEDDED);
    cb.SetColorFill(iTextSharp.text.Color.BLACK);
    cb.SetFontAndSize(baseFontBold, 14);

    cb.BeginText();
    cb.ShowTextAligned(PdfContentByte.ALIGN_LEFT, "TEST!!", 385, 750, 0);
    cb.EndText();

    cb.SetColorStroke(new CMYKColor(0f, 0f, 0f, 1f));
    cb.SetColorFill(new CMYKColor(0f, 0f, 0f, 1f));

    cb.MoveTo(139, 398);
    cb.LineTo(146, 398);
    cb.LineTo(146, 391);
    cb.LineTo(139, 391);
    cb.ClosePathEoFillStroke();

    pdfStamper.Close();
    pdfReader.Close();
}

但是为什么呢?如果用户愿意，我宁愿将其全部保存在内存中，并让用户保存生成的 PDF，而不必将其写入磁盘然后显示.

But why? I'd rather keep it all in memory and let the user save the resulting PDF if he/she so wishes than having to write it to disk and then displaying it.