public static string[] FilteringSenders(IEnumerable <GeneralPhone> phones) { IEnumerable <SmsMessage> allSms = new SmsMessage[0]; foreach (IPhone phone in phones) { allSms = allSms.Concat(phone.UseComponent <Memory>().Get <SmsMessage>()); } var receivedFrom = allSms.Where(c => c.ReceivedFrom != null).Select(c => c.ReceivedFrom).Distinct(); return(new List <string>() { FILTER_ALL_VALUES }.Concat(receivedFrom).ToArray()); }