With the code below, how can i send PDF which has a rendered image to an email

    protected void Button3_Click(object sender, EventArgs e)
    {
        string fileName = "Invoice" + DateTime.Now.ToString() + ".pdf";

        byte[] QRBytes = GetQRCodeBytes(Server.MapPath("/InvoiceDoc.aspx") + "?Id=" + Session["Invoice"]);
        Image1.ImageUrl = "data:image/jpg;base64," + Convert.ToBase64String(QRBytes);
        var ImgUrl = Image1.ImageUrl;
        // Write image as file to folder.
        File.WriteAllBytes(Server.MapPath("qrimg.jpg"), QRBytes);
        // convert and set absolute url in image.
        Image1.ImageUrl = GetUrl("qrimg.jpg");

        StringWriter sw = new StringWriter();
        HtmlTextWriter hw = new HtmlTextWriter(sw);
        Panel1.RenderControl(hw);
        StringReader sr = new StringReader(sw.ToString());
        Document pdfDoc = new Document(PageSize.A4, 10f, 10f, 10f, 10f);
        PdfWriter PdfWriter = PdfWriter.GetInstance(pdfDoc, Response.OutputStream);
        HtmlPipelineContext htmlContext = new HtmlPipelineContext(null);
        htmlContext.SetTagFactory(Tags.GetHtmlTagProcessorFactory());
        ICSSResolver cssResolver = XMLWorkerHelper.GetInstance().GetDefaultCssResolver(false);
        cssResolver.AddCssFile(Server.MapPath("~/css/style2.css"), true);
        IPipeline pipeline = new CssResolverPipeline(cssResolver, new HtmlPipeline(htmlContext, new PdfWriterPipeline(pdfDoc, PdfWriter)));
        var worker = new XMLWorker(pipeline, true);
        var xmlParse = new XMLParser(true, worker);
        pdfDoc.Open();
        xmlParse.Parse(sr);
        xmlParse.Flush();
        pdfDoc.Close();
        Response.ContentType = "application/pdf";
        Response.AddHeader("content-disposition", "attachment;filename=" + fileName + ";");
        Response.Cache.SetCacheability(HttpCacheability.NoCache);
        Response.Write(pdfDoc);
        // Delete the temp image.
        File.Delete(Server.MapPath("qrimg.jpg"));
        Image1.ImageUrl = ImgUrl;
        Response.End();
    }