ItextSharp 将行添加到 PDF 并转换为字节而不保存。

Question

我有一个方法可以获取 pdf 并在该 pdf 中添加行，然后创建一个新的 pdf 并将其保存在给定的路径中。现在我不想将该新文件保存在路径中，而是想将其转换为字节并在电子邮件中发送我该怎么做？编码。

     protected void CreatePDF()
    {

        string Oldfile = @"C:\BlankPDFt.pdf"; // Gets the Template / The actualy agreement Letter
      //  (new FileInfo("C:/Documents/Docs.pdf")).Directory.Create(); // Go create this folder if it's not there
      string NewFile = "C:/Documents/Docs.pdf";
        PdfReader reader = new PdfReader(Oldfile);
        iTextSharp.text.Rectangle Size = reader.GetPageSizeWithRotation(1);
        Document document = new Document(Size);
        FileStream fs = new FileStream(NewFile , FileMode.Create, FileAccess.Write); // This is where it all ways look for new file path
 i dont want it to save instead convert to bytes but wont work.
        PdfWriter weiter = PdfWriter.GetInstance(document, fs);
        document.Open();
        PdfContentByte cb = weiter.DirectContent;
        PdfImportedPage page = weiter.GetImportedPage(reader, 1);
        cb.AddTemplate(page, 0, 0);
        BaseFont bf = BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.CP1252, BaseFont.NOT_EMBEDDED);
        cb.SetColorFill(BaseColor.BLACK);
        cb.SetFontAndSize(bf, 12);
        cb.BeginText();
     //   string Signatur = "Some texts"; // adds this text to that pdf 
      cb.ShowTextAligned(PdfContentByte.ALIGN_CENTER, "Here", 335, 90, 0); // Insert the signature
        cb.EndText();
    }

Answer 1

PdfWriter.GetInstance() 方法接受 InputStream 作为其第二个参数。而不是传递一个FileStream，你应该传递一个MemoryStream。

MemoryStream memory_stream = new MemoryStream();
PdfWriter.GetInstance(document, memory_stream );
...
document.Close();
byte[] pdf_bytes = memory_stream.ToArray();