public static string RequestNumberInputFromUser(string userPrompt) { string UserInput; bool conformsToRules = false; // We check input for a Digit do { Console.Write(userPrompt); UserInput = Console.ReadLine(); // Get user input conformsToRules = UserInput.All(x => char.IsDigit(x)); if (!conformsToRules) { Console.WriteLine(Strings.UserIsDumb); } } while (!conformsToRules); return(UserInput); }