string fromemailid;
            string from_email_pwd;
            fromemailid = "myemail@gmail.com";
            from_email_pwd = "*******xyz";
            MailAddress fromaddress = new MailAddress(fromemailid);
            MailAddress toaddress = new MailAddress("example@gmail.com");
            MailMessage msg = new MailMessage(fromaddress, toaddress);
            msg.Subject = ("newdemo");
            msg.Body = ("ok ");
            msg.Priority = MailPriority.High;
            System.Net.Mail.SmtpClient mailsender = new System.Net.Mail.SmtpClient("smtp.gmail.com", 587);
            System.Net.NetworkCredential mailauthantication = new System.Net.NetworkCredential(fromemailid, from_email_pwd);
            mailsender.EnableSsl = true;
            mailsender.UseDefaultCredentials = false;
            mailsender.Credentials = mailauthantication;
            mailsender.Send(msg);
            string display = "Done Check your Mail !";
            ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "alertMessage", "sweetAlert('" + display + "','','success')", true);