C#给PDF文件添加水印

 using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using iTextSharp.text.html.simpleparser; using iTextSharp.text.pdf; using iTextSharp.text; using System.IO; using System.Web.UI.HtmlControls; using System.Drawing; //itextsharp.dll version:5.1.10 protected void Button1_Click(object sender, EventArgs e) { string source =@"D:\My.Sample\C#NET\Exoport2PDF\Web2\Chap1011.pdf"; //模板路径 string output = @"D:\My.Sample\C#NET\Exoport2PDF\Web2\Chap1012.pdf"; //导出水印背景后的PDF string watermark = @"D:\My.Sample\C#NET\Exoport2PDF\Web2\gp0.jpg-600"; // 水印图片 bool isSurrcess = PDFWatermark(source, output, watermark, 10, 10); } public 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 - image.Width + left; } image.SetAbsolutePosition(left, (height - 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); waterMarkContent.AddImage(image); } //strMsg = "success"; return true; } catch (Exception ex) { ex.Message.Trim(); return false; } finally { if (pdfStamper != null) pdfStamper.Close(); if (pdfReader != null) pdfReader.Close(); }