Grid view print

Question

grvcourse.AllowPaging = false;

grvcourse.DataBind();

StringWriter sw = new StringWriter();

HtmlTextWriter hw = new HtmlTextWriter(sw);

grvcourse.RenderControl(hw);

string gridHTML = sw.ToString().Replace("\"", "'")

.Replace(System.Environment.NewLine, "");

StringBuilder sb = new StringBuilder();

sb.Append("<script type = 'text/javascript'>");

sb.Append("window.onload = new function(){");

sb.Append("var printWin = window.open('', '', 'left=0");

sb.Append(",top=0,width=300,height=300,status=0');");

sb.Append("printWin.document.write(\"");

sb.Append(gridHTML);

sb.Append("\");");

sb.Append("printWin.document.close();");

sb.Append("printWin.focus();");

sb.Append("printWin.print();");

sb.Append("printWin.close();};");

sb.Append("</script>");

ClientScript.RegisterStartupScript(this.GetType(), "GridPrint", sb.ToString());

grvcourse.AllowPaging = true;

grvcourse.DataBind();

This is my code.The printing process is work , but after the printing, there is nothing in printed file. Is like blank.

Can anyone help me?

Thanks a lot for viewing my post. :-)