Send PDF with email in ASP.Net

Thanks for your kind Reply,However it was needed for me to save the pdf doc in server and attach the same with the email every time when payment done,

I would like to share how I did that.

private void Sendpdf(string OrderID)
{
    try
    {
        ThankYou_BLL obj = new ThankYou_BLL();
        dspdf = obj.ThankUdetails(OrderID);
        if (dspdf.Tables[0].Rows.Count > 0)
        {
            lblName.Text = dspdf.Tables[0].Rows[0]["FullNme"].ToString();
            lblICNo.Text = dspdf.Tables[0].Rows[0]["NewICNo"].ToString();
            lblEmail.Text = dspdf.Tables[0].Rows[0]["Email"].ToString();
            lblType.Text = dspdf.Tables[0].Rows[0]["ProgramName"].ToString();
            lblAmount.Text = "RM" + "" + dspdf.Tables[0].Rows[0]["Amount"].ToString();
            lblOrderID.Text = dspdf.Tables[0].Rows[0]["OrderId"].ToString();
            lblRegistrationDt.Text = dspdf.Tables[0].Rows[0]["JoinDate"].ToString();
 
 
            Response.ContentType = "application/pdf";
            Response.AddHeader("content-disposition", "attachment;filename=Panel.pdf");
            Response.Cache.SetCacheability(HttpCacheability.NoCache);
            StringWriter sw = new StringWriter();
            HtmlTextWriter hw = new HtmlTextWriter(sw);
            pnlPerson.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);
            PdfWriter.GetInstance(pdfDoc, new FileStream(Context.Server.MapPath("~/PdfDoc/PaymentDetails.pdf"), FileMode.Create));
 
            pdfDoc.Open();
            htmlparser.Parse(sr);
            pdfDoc.Close();
            //Response.Write(pdfDoc);
            //Response.End();
        }
    }
    catch (Exception)
    {         
        throw;
    } 
}

attahment the saved pdf like this.

Attachment mailattach = new Attachment(Path.GetFullPath(Context.Server.MapPath("~/PdfDoc/PaymentDetails.pdf")));