Timespan Start Stop Clock

DateTime dStopCLock = DateTime.Now;
TimeSpan ts = dStartCLock - dStopCLock;
double differenceInSeconds = ts.TotalSeconds;
ts = TimeSpan.FromSeconds(ts.TotalSeconds);
 
string sDuration = string.Format("Dur: {0:D2}h:{1:D2}m:{2:D2}s",
             ts.Hours,
             ts.Minutes,
             ts.Seconds);
Console.WriteLine(sDuration);