unable to export pdf gridview with image

Question

StringWriter sw = new StringWriter();

HtmlTextWriter hw = new HtmlTextWriter(sw);

hw.AddStyleAttribute("font-size", "10pt");

hw.AddStyleAttribute("font-weight", "none");

hw.AddStyleAttribute("color", "Black");

pnlContents.RenderControl(hw);

StringReader sr = new StringReader(sw.ToString());

Document pdfDoc = new Document(PageSize.A4, 20f, 10f, 10f, 0f);

PdfWriter writer = PdfWriter.GetInstance(pdfDoc, Response.OutputStream);

pdfDoc.Open();

XMLWorkerHelper.GetInstance().ParseXHtml(writer, pdfDoc, sr);

pdfDoc.Close();

Response.ContentType = "application/pdf";

Response.AddHeader("content-disposition", "attachment;filename=Result.pdf");

Response.Cache.SetCacheability(HttpCacheability.NoCache);

Response.Write(pdfDoc);

Response.End();

 

 

 

this mys codes