/*method validateMail*/
        public bool validateMail(string Mailadress)
        {
            string mailPattern = @"^[\w\._]{1,}@[\w\._]{2,}\.\w{2,4}$”;
            Regex re = new Regex(mailPattern);
            Match ma = re.Match(Mailadress);
            if (ma.Success)
                return true;
            else
                return false;
        }