class Program { enum Fruits { @apple = -1, Apple = 1, Grapes = 2, Orange = 3 }; static void getfruit(Fruits f) { Console.WriteLine(f); } static void getfruit(Nullable<Fruits> f = Fruits.@apple) { try { Console.WriteLine(f); } catch { Console.WriteLine("Null"); } } static void Main(string[] args) { getfruit(Fruits.Apple); getfruit(); Console.Read(); } }