/// <summary>/// 将PDF文档转换为图片的方法/// </summary>/// <param name="pdfInputPath"></param>/// <param name="desPath">输出相对路径</param>/// <param name="definition">设置图片的清晰度，数字越大越清晰</param>/// <returns></returns>public static List<string> ConvertPDF2Image(string pdfInputPath, string desPath, Definition definition, string title){List<string> imgList = new List<string>();PDFFile pdfFile = PDFFile.Open(pdfInputPath);int startPageNum = 1, endPageNum = pdfFile.PageCount;int number = 1;for (int i = startPageNum; i <= endPageNum; i++){Bitmap pageImage = pdfFile.GetPageImage(i - 1, 56 * (int)definition);string filePath = desPath + title + "-" + number + ".jpg";imgList.Add(filePath);pageImage.Save(System.Web.HttpContext.Current.Server.MapPath(filePath));number++;}pdfFile.Dispose();return imgList;}public enum Definition{One = 1, Two = 2, Three = 3, Four = 4, Five = 5, Six = 6, Seven = 7, Eight = 8, Nine = 9, Ten = 10}/// <summary>/// 合并PDF/// </summary>/// <param name="fileList">绝对路径集合</param>/// <param name="outMergeFile">合并后的文件存在地址绝对路径</param>public static void mergePdfFiles(List<string> fileList, string outMergeFile){PdfReader reader;//此处将内容从文本提取至文件流中的目的是避免文件被占用,无法删除FileStream fs1 = new FileStream(fileList[0], FileMode.Open);byte[] bytes1 = new byte[(int)fs1.Length];fs1.Read(bytes1, 0, bytes1.Length);fs1.Close();reader = new PdfReader(bytes1);reader.GetPageSize(1);// iTextSharp.text.Rectangle rec = new iTextSharp.text.Rectangle(1000,800);//设置样式iTextSharp.text.Rectangle rec = reader.GetPageSize(1);float width = rec.Width;float height = rec.Height;//创建一个文档变量iTextSharp.text.Document document = new iTextSharp.text.Document(rec, 50, 50, 50, 50);//创建该文档PdfWriter pdfWrite = PdfWriter.GetInstance(document, new FileStream(outMergeFile, FileMode.Create));//打开文档
            document.Open();//添加内容PdfContentByte contentByte = pdfWrite.DirectContent;PdfImportedPage newPage;for (int i = 0; i < fileList.Count; i++){FileStream fs = new FileStream(fileList[i], FileMode.Open);byte[] bytes = new byte[(int)fs.Length];fs.Read(bytes, 0, bytes.Length);fs.Close();reader = new PdfReader(bytes);int pageNum = reader.NumberOfPages;//获取文档页数for (int j = 1; j <= pageNum; j++){document.NewPage();newPage = pdfWrite.GetImportedPage(reader, j);contentByte.AddTemplate(newPage, 0, 0);}}document.Close();}

        /// <summary>/// 图片转PDF/// </summary>/// <param name="imagepath">图片位置（绝地路径）</param>/// <param name="pdfpath">存放PDF地址（绝地路径）</param>public static void iTextSharpCreatPDF(string imagepath, string pdfpath){iTextSharp.text.Image image = iTextSharp.text.Image.GetInstance(imagepath);float percentage = 1;//这里都是图片最原始的宽度与高度float resizedWidht = image.Width;float resizedHeight = image.Height;Document doc = new Document(new iTextSharp.text.Rectangle(resizedWidht, resizedHeight), 0, 0, 0, 0); //new Rectangle(1000,1000)//指定文件预设开档时的缩放为100%//PdfDestination pdfDest = new PdfDestination(PdfDestination.XYZ, 0, doc.PageSize.Height, 1f);try{PdfWriter.GetInstance(doc, new FileStream(pdfpath, FileMode.Create));doc.Open();#region 下面对图片进行操作////这时判断图片宽度是否大于页面宽度减去也边距，如果是，那么缩小，如果还大，继续缩小，////这样这个缩小的百分比percentage会越来越小while (resizedWidht > (doc.PageSize.Width - doc.LeftMargin - doc.RightMargin)){percentage = percentage * 0.9f;resizedHeight = image.Height * percentage;resizedWidht = image.Width * percentage;}#region 注释////There is a 0.8 here. If the height of the image is too close to the page size height,////the image will seem so big//while (resizedHeight > (doc.PageSize.Height - doc.TopMargin - doc.BottomMargin) * 0.8)//{//    percentage = percentage * 0.9f;//    resizedHeight = image.Height * percentage;//    resizedWidht = image.Width * percentage;//}#endregion////这里用计算出来的百分比来缩小图片image.ScalePercent(percentage * 100);//让图片的中心点与页面的中心点进行重合image.SetAbsolutePosition(doc.PageSize.Width / 2 - resizedWidht / 2, doc.PageSize.Height / 2 - resizedHeight / 2);doc.Add(image);#endregion}catch (DocumentException dex){System.Web.HttpContext.Current.Response.Write(dex.Message);}catch (IOException ioex){System.Web.HttpContext.Current.Response.Write(ioex.Message);}catch (Exception ex){System.Web.HttpContext.Current.Response.Write(ex.Message);}finally{doc.Close();}}