c # function to test HHMM

function to test HHMM -- HoursMins using regular expression (REGEX)

private string TestHHMM()

{

string InputString = DateTime.Now.ToString("HHmm"); // "2200";

if (InputString.Length >= 2)

InputString = InputString.PadLeft(4, '0');

Regex RegexObj = new Regex("^([0-1]\\d

2[0-3])([0-5][0-9])$");

if (RegexObj.IsMatch(InputString))

Console.WriteLine("true");

else

Console.WriteLine("false");

return RegexObj.Replace(InputString, "$1:$2");
}