Validare indirizzo E-Mail con le Regex

public static bool ValidaEMail(string strIn) {     if (String.IsNullOrEmpty(strIn))         return false;     return Regex.IsMatch(strIn,             @"^(?("")(""[^""]+?""@)|(([0-9a-z]((\.(?!\.))|[-!#\$%&'\*\+/=\?\^`\{\}\|~\w])*)(?<=[0-9a-z])@))" +             @"(?(\[)(\[(\d{1,3}\.){3}\d{1,3}\])|(([0-9a-z][-\w]*[0-9a-z]*\.)+[a-z0-9]{2,17}))$",             RegexOptions.IgnoreCase); }