public bool IsSpam(string countryCode) { if (!System.Enum.IsDefined(typeof(CountryWhiteList), Extension.ToUpper()) || !System.Enum.IsDefined(typeof(CountryWhiteList), countryCode.ToUpper())) { Validity += "Extension or IP country code is not valid.\n"; IsValid = false; } if (Identifier.Count(Char.IsLetter) <= Identifier.Count(char.IsDigit)) { Validity += "Identifier should have more letters than digits.\n"; IsValid = false; } if (Domains.Count() > 3) { Validity += "Number of Domains should be less than 3.\n"; IsValid = false; } return(IsValid); }