public static void Main()
string fmt3 = "##;(##);**Zero**";
Console.WriteLine(posValue.ToString(fmt1));
Console.WriteLine(negValue.ToString(fmt1));
Console.WriteLine(posValue.ToString(fmt2));
Console.WriteLine(String.Format("{0:" + fmt2 + "}", posValue));
Console.WriteLine(negValue.ToString(fmt2));
Console.WriteLine(String.Format("{0:" + fmt2 + "}", negValue));
Console.WriteLine(zeroValue.ToString(fmt3));
Console.WriteLine(String.Format("{0:" + fmt3 + "}", zeroValue));