Convert web page content to pdf file in asp.net

Question

Hi Friend,

I am developing web application form for offer letter issued.

In that web page after i enter all details click button it will show direct print  but, i need direct convert that content page(panel)to PDF file in asp.net using c# coding.

In that web page i am using calendar control also convert to PDF(inside panel) file.

Please any one give immediate solution.

This is my Coding:

  Panel1.Visible = true;
        Label1.Text = TextBox1.Text;
        Label2.Text = TextBox2.Text;
        System.Globalization.DateTimeFormatInfo dateInfo = new System.Globalization.DateTimeFormatInfo();
        dateInfo.ShortDatePattern = "dd/MM/yyyy";
        DateTime doj = Convert.ToDateTime(TextBox2.Text, dateInfo);

        Response.ContentType = "application/pdf";
        Response.AddHeader("content-disposition", "attachment;filename=TestPage.pdf");
        Response.Cache.SetCacheability(HttpCacheability.NoCache);
        StringWriter sw = new StringWriter();
        HtmlTextWriter hw = new HtmlTextWriter(sw);
        this.Page.RenderControl(hw);
        StringReader sr = new StringReader(sw.ToString());
        Document pdfDoc = new Document(PageSize.A4, 10f, 10f, 100f, 0f);
        HTMLWorker htmlparser = new HTMLWorker(pdfDoc);
        PdfWriter.GetInstance(pdfDoc, Response.OutputStream);
        pdfDoc.Open();
        htmlparser.Parse(sr);
        pdfDoc.Close();
        Response.Write(pdfDoc);
        Response.End();       

But it will show Error like this,

Extender control 'CalendarExtender1' is not a registered extender control. Extender controls must be registered using RegisterExtenderControl() before calling RegisterScriptDescriptors().
Parameter name: extenderControl

How i can solve this error please any one give immediate solution.