private bool IsValidEmail(string mailDenetim) { // Return true if strIn is in valid e-mail format. return Regex.IsMatch(mailDenetim, @"^([\w-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$"); }