BrowserSelect.AutoMatchRule.error C# (CSharp) Метод

        public string error()
        {
            if (!string.IsNullOrEmpty(Pattern))
                return string.Format("You forgot to select a Browser for '{0}' rule.", Pattern);
            else if (!string.IsNullOrEmpty(Browser))
                return "one of your rules has an Empty pattern. please refer to Help for more information.";
            else
                return "";
        }