将IMAGE转为PDF后上传

　　　　　using iTextSharp.text;
　　　　　using iTextSharp.text.pdf;

　　　　　/// <summary>
        /// 将IMAGE转为PDF后上传
        /// </summary>
        /// <param name="img"></param>
        /// <param name="strUpLoadPdfPath"></param>
        /// <param name="strNewFileName"></param>
        /// <param name="imgFormat"></param>
        public void uploadImageToPdf(System.Drawing.Image img, string strUpLoadPdfPath, ref string strNewFileName, System.Drawing.Imaging.ImageFormat imgFormat = null)
        {
            try
            {
                if (imgFormat == null)
                {
                    imgFormat = System.Drawing.Imaging.ImageFormat.Jpeg;
                }
                //PDF存档路径
                if (strUpLoadPdfPath.LastIndexOf(@"\") == strUpLoadPdfPath.Length - 1)
                {
                    strUpLoadPdfPath = strUpLoadPdfPath.Substring(0, strUpLoadPdfPath.Length - 1);
                }
                if (strNewFileName.Trim() == "")
                {
                    strNewFileName = DateTime.Now.ToString("yyyyMMddHHmm");
                }
                strNewFileName = strUpLoadPdfPath + @"\" + strNewFileName;
                if (!strNewFileName.ToLower().Contains(".pdf"))
                {
                    strNewFileName += ".pdf";
                }

                if (!Directory.Exists(strUpLoadPdfPath))
                {
                    Directory.CreateDirectory(strUpLoadPdfPath);
                }

                //定义pdf大小，设置上下左右边距
                iTextSharp.text.Document doc = new iTextSharp.text.Document(iTextSharp.text.PageSize.A3, 15, 15, 20, 20);
                //设置保存路径  
                PdfWriter writer = PdfWriter.GetInstance(doc, new FileStream(strNewFileName, FileMode.Create));

                //生成pdf路径，创建文件流              
                doc.Open();
                //将图片写入PDF中
                iTextSharp.text.Image imgSave = iTextSharp.text.Image.GetInstance(img, imgFormat);
                imgSave.Alignment = iTextSharp.text.Image.ALIGN_MIDDLE;
                imgSave.ScaleAbsolute(750f, 1150f);
                doc.Add(imgSave);
                //保存PDF文件
                writer.Flush();
                writer.CloseStream = true;
                doc.Close();
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }