iTextSharp简单生成pdf和操作pdf添加水印

iTextSharp,a .NET PDF library 。iTextSharp.dll 下载地址 https://sourceforge.net/projects/itextsharp/

iText is a PDF library that allows you to CREATE, ADAPT, INSPECT and MAINTAIN documents in the Portable Document Format (PDF):
- Generate documents and reports based on data from an XML file or a database
- Create maps and books, exploiting numerous interactive features available in PDF
- Add bookmarks, page numbers, watermarks, and other features to existing PDF documents
- Split or concatenate pages from existing PDF files
- Fill out interactive forms
- Serve dynamically generated or manipulated PDF documents to a web browser

iText is used by Java, .NET, Android and GAE developers to enhance their applications with PDF functionality.
iTextSharp is the .NET port.

Several iText engineers are actively supporting the project on on StackOverflow: http://stackoverflow.com/questions/tagged/itext

IMPORTANT NOTICE: AS OF 2016-03-14, ITEXTSHARP DOWNLOADS AND SOURCE CODE WILL ONLY BE AVAILABLE ON GITHUB:http://github.com/itext

以下转自 http://www.cnblogs.com/LL-723/archive/2013/12/25/3490699.html （先引入itextsharp.dll ， 5.5.9.0版大小是3.86M）

public class PDFSetWaterMark    {        /// <summary>        /// 创建一个显示指定图片的pdf        /// </summary>        /// <param name="picPdfPath"></param>        /// <param name="picPath"></param>        /// <returns></returns>        public static bool CreatePDFByPic(string picPdfPath,string picPath)        {            //新建一个文档            Document doc = new Document();            try            {                //建立一个书写器(Writer)与document对象关联                PdfWriter.GetInstance(doc, new FileStream(picPdfPath, FileMode.Create, FileAccess.ReadWrite));                //打开一个文档                doc.Open();                //向文档中添加内容                Image img = Image.GetInstance(picPath);                //img.SetAbsolutePosition();                doc.Add(img);                return true;            }            catch (Exception ex)            {                return false;                throw ex;            }            finally            {                if (doc != null)                {                    doc.Close();                }            }        }        /// <summary>        /// 加图片水印        /// </summary>        /// <param name="inputfilepath"></param>        /// <param name="outputfilepath"></param>        /// <param name="ModelPicName"></param>        /// <param name="top"></param>        /// <param name="left"></param>        /// <returns></returns>        public static bool PDFWatermark(string inputfilepath, string outputfilepath, string ModelPicName, float top, float left)        {            //throw new NotImplementedException();            PdfReader pdfReader = null;            PdfStamper pdfStamper = null;            try            {                pdfReader = new PdfReader(inputfilepath);                int numberOfPages = pdfReader.NumberOfPages;                iTextSharp.text.Rectangle psize = pdfReader.GetPageSize(1);                float width = psize.Width;                float height = psize.Height;                pdfStamper = new PdfStamper(pdfReader, new FileStream(outputfilepath, FileMode.Create));                PdfContentByte waterMarkContent;                iTextSharp.text.Image image = iTextSharp.text.Image.GetInstance(ModelPicName);                image.GrayFill = 20;//透明度，灰色填充                //image.Rotation//旋转                //image.RotationDegrees//旋转角度                //水印的位置                 if (left < 0)                {                    left = width/2 - image.Width + left;                }                //image.SetAbsolutePosition(left, (height - image.Height) - top);                image.SetAbsolutePosition(left, (height/2 - image.Height) - top);                //每一页加水印,也可以设置某一页加水印                 for (int i = 1; i <= numberOfPages; i++)                {                    //waterMarkContent = pdfStamper.GetUnderContent(i);//内容下层加水印                    waterMarkContent = pdfStamper.GetOverContent(i);//内容上层加水印                    waterMarkContent.AddImage(image);                }                //strMsg = "success";                return true;            }            catch (Exception ex)            {                throw ex;                            }            finally            {                if (pdfStamper != null)                    pdfStamper.Close();                if (pdfReader != null)                    pdfReader.Close();            }        }        /// <summary>        /// 添加普通偏转角度文字水印        /// </summary>        /// <param name="inputfilepath"></param>        /// <param name="outputfilepath"></param>        /// <param name="waterMarkName"></param>        /// <param name="permission"></param>        public static void setWatermark(string inputfilepath, string outputfilepath,string waterMarkName)        {            PdfReader pdfReader = null;            PdfStamper pdfStamper = null;            try            {                pdfReader = new PdfReader(inputfilepath);                pdfStamper = new PdfStamper(pdfReader, new FileStream(outputfilepath, FileMode.Create));                int total = pdfReader.NumberOfPages + 1;                iTextSharp.text.Rectangle psize = pdfReader.GetPageSize(1);                float width = psize.Width;                float height = psize.Height;                PdfContentByte content;                BaseFont font = BaseFont.CreateFont(@"C:\WINDOWS\Fonts\SIMFANG.TTF", BaseFont.IDENTITY_H, BaseFont.EMBEDDED);                PdfGState gs = new PdfGState();                for (int i = 1; i < total; i++)                 {                    content = pdfStamper.GetOverContent(i);//在内容上方加水印                    //content = pdfStamper.GetUnderContent(i);//在内容下方加水印                    //透明度                    gs.FillOpacity = 0.3f;                    content.SetGState(gs);                    //content.SetGrayFill(0.3f);                    //开始写入文本                    content.BeginText();                    content.SetColorFill(BaseColor.LIGHT_GRAY);                    content.SetFontAndSize(font, 100);                    content.SetTextMatrix(0, 0);                    content.ShowTextAligned(Element.ALIGN_CENTER, waterMarkName, width / 2 - 50,height / 2 - 50, 55);                    //content.SetColorFill(BaseColor.BLACK);                    //content.SetFontAndSize(font, 8);                    //content.ShowTextAligned(Element.ALIGN_CENTER, waterMarkName, 0, 0, 0);                    content.EndText();                }            }catch (Exception ex)            {                throw ex;            }            finally            {                if (pdfStamper != null)                    pdfStamper.Close();                if (pdfReader != null)                    pdfReader.Close();            }        }        /// <summary>        /// 添加倾斜水印        /// </summary>        /// <param name="inputfilepath"></param>        /// <param name="outputfilepath"></param>        /// <param name="waterMarkName"></param>        /// <param name="userPassWord"></param>        /// <param name="ownerPassWord"></param>        /// <param name="permission"></param>        public static void setWatermark(string inputfilepath, string outputfilepath, string waterMarkName, string userPassWord, string ownerPassWord, int permission)        {            PdfReader pdfReader = null;            PdfStamper pdfStamper = null;            try            {                pdfReader = new PdfReader(inputfilepath);                pdfStamper = new PdfStamper(pdfReader, new FileStream(outputfilepath, FileMode.Create));                // 设置密码                   //pdfStamper.SetEncryption(false,userPassWord, ownerPassWord, permission);                 int total = pdfReader.NumberOfPages + 1;                PdfContentByte content;                BaseFont font = BaseFont.CreateFont(@"C:\WINDOWS\Fonts\SIMFANG.TTF", BaseFont.IDENTITY_H, BaseFont.EMBEDDED);                PdfGState gs = new PdfGState();                gs.FillOpacity = 0.2f;//透明度                int j = waterMarkName.Length;                char c;                int rise = 0;                for (int i = 1; i < total; i++)                {                    rise = 500;                    content = pdfStamper.GetOverContent(i);//在内容上方加水印                    //content = pdfStamper.GetUnderContent(i);//在内容下方加水印                                        content.BeginText();                    content.SetColorFill(BaseColor.DARK_GRAY);                    content.SetFontAndSize(font, 50);                    // 设置水印文字字体倾斜 开始                     if (j >= 15)                    {                        content.SetTextMatrix(200, 120);                        for (int k = 0; k < j; k++)                        {                            content.SetTextRise(rise);                            c = waterMarkName[k];                            content.ShowText(c + "");                            rise -= 20;                        }                    }                    else                    {                        content.SetTextMatrix(180, 100);                        for (int k = 0; k < j; k++)                        {                            content.SetTextRise(rise);                            c = waterMarkName[k];                            content.ShowText(c + "");                            rise -= 18;                        }                    }                    // 字体设置结束                     content.EndText();                    // 画一个圆                     //content.Ellipse(250, 450, 350, 550);                    //content.SetLineWidth(1f);                    //content.Stroke();                 }             }            catch (Exception ex)            {                throw ex;            }            finally            {                if (pdfStamper != null)                    pdfStamper.Close();                if (pdfReader != null)                    pdfReader.Close();            }        }    }

调用的例子：

string path = "E://3.pdf";                HtmlToPDFUtil.HtmlToPdf(Request.Url.AbsoluteUri, path);                //HtmlToPDFUtil.HtmlToPdf(sbUrlList.ToString(), path);                PDFSetWaterMark.PDFWatermark(path, "E://3-1.pdf", Server.MapPath("/HtmlToPdf/Tools/sy.bmp"), 0, 0);                PDFSetWaterMark.setWatermark("E://3-1.pdf", "E://3-2.pdf", "ssss");                //PDFSetWaterMark.setWatermark("E://3-2.pdf", "E://3-3.pdf", "sssss", "", "", 1);