public static bool ValidateEmail(string StreMail)
{
if (StreMail.Length == 0) return true;
System.Text.RegularExpressions.Regex rEmail = new System.Text.RegularExpressions.Regex(@"\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*");
if (rEmail.IsMatch(StreMail)) return true;
return false;
}