C#生成PDF文件流

static BaseFont FontBase = BaseFont.CreateFont("C://WINDOWS//FONTS//STSONG.TTF", BaseFont.IDENTITY_H, BaseFont.EMBEDDED);    static iTextSharp.text.Font bodyFont = new iTextSharp.text.Font(FontBase, 12);    static iTextSharp.text.Font titleFont = new iTextSharp.text.Font(FontBase, 18);    static iTextSharp.text.Font paragraphFont = new iTextSharp.text.Font(FontBase, 15);    static iTextSharp.text.Font linkFont = new iTextSharp.text.Font(FontBase, 12, Font.UNDERLINE, BaseColor.BLUE);

public byte[] DocCreate(System.Drawing.Image image, List<TreeNodes> list)    {      MemoryStream file = new MemoryStream();      string fileName = string.Empty;      Rectangle page = PageSize.A4;      float y = page.Height;      Document document = new Document(page, 15, 15, 30, 30);      float docWidth = page.Width - 15 * 2;      float docHeight = page.Height - document.BottomMargin - document.TopMargin;      PdfWriter writer = PdfWriter.GetInstance(document, file);      writer.CloseStream = false;      writer.Open();      PdfContentByte cb = writer.DirectContent;      document.Open();      //标题      Paragraph      title.Alignment = Element.ALIGN_CENTER;      document.Add(title);      //图片      iTextSharp.text.Image img = iTextSharp.text.Image.GetInstance(image, ImageFormat.Png);      float widthSzie = (page.Width - 30) / img.Width;      if (widthSzie < 1)      {        img.ScalePercent(widthSzie * 100);      }      document.Add(img);      //文献出处      Paragraph p2 = new Paragraph(new Chunk("出处", paragraphFont));      p2.IndentationLeft = indentationLeft;      document.Add(p2);      InitData(list);//初始化业务数据      CreateSteps(list, document, list.FirstOrDefault(it => it.PID == 0));//添加业务数据      ////添加印章      //iTextSharp.text.Image whyz = iTextSharp.text.Image.GetInstance(whyzPath);      //whyz.ScalePercent(50);      //whyz.PaddingTop = 100;      //whyz.Alignment = Element.ALIGN_RIGHT;      //document.Add(whyz);      //添加日期      Paragraph createtime = new Paragraph(new Chunk(DateTime.Now.ToLongDateString().ToString(), bodyFont));      createtime.Alignment = Element.ALIGN_RIGHT;      //createtime.SpacingBefore = -80;      createtime.PaddingTop = 200;      document.Add(createtime);      document.Close();      file.Position = 0;      MemoryStream newfile = SetWaterMark(file, "水印内容", docWidth, docHeight);//添加水印，见另外一篇博客      newfile.Position = 0;//重置流指针位置      byte[] bytes = new byte[newfile.Length];      newfile.Read(bytes, 0, bytes.Length);      return bytes;    }