public static void Main()
var test = DateTime.Now.ToString("hh:mm:ss");
var test2 = DateTime.Now.ToString(@"hh\:mm\:ss");
Console.WriteLine(test2);
var test3 = TimeSpan.FromHours(10).ToString("hh:mm:ss");
Console.WriteLine(test3);
var test4 = TimeSpan.FromHours(10).ToString(@"hh\:mm\:ss");
Console.WriteLine(test4);