LinqPad.TimedTest

public static void TimedTest(Action action, string message = "", int decimalPlaces = 1)
{
  var stopwatch = new Stopwatch();

  stopwatch.Start();

  action.Invoke();

  stopwatch.Stop();

  double elapsed = stopwatch.ElapsedTicks / Stopwatch.Frequency;

  var time = stopwatch.ElapsedTicks * 1e-9 + " ms" + " (" + stopwatch.ElapsedTicks + " ticks)";

  if (String.IsNullOrWhiteSpace(message))
    Console.WriteLine("Elapsed time: " + time);
  else
    Console.WriteLine(string.Format("{0} (Elapsed time: {1})", message, time));
}

public static void TimedTest(Action action, string message = "", int decimalPlaces = 1)
{
  var stopwatch = new Stopwatch();

  stopwatch.Start();

  action.Invoke();

  stopwatch.Stop();

  // ReSharper disable once PossibleLossOfFraction
  double elapsed = stopwatch.ElapsedTicks / Stopwatch.Frequency;

  string time;

  if (elapsed > 1)
    time = Math.Round(elapsed, decimalPlaces) + " s";
  else if (elapsed > 1e-3)
    time = Math.Round(1e3 * elapsed, decimalPlaces) + " ms";
      else if (elapsed > 1e-6)
        time = Math.Round(1e6 * elapsed, decimalPlaces) + " µs";
      else if (elapsed > 1e-9)
        time = Math.Round(1e9 * elapsed, decimalPlaces) + " ns";
      else
        time = stopwatch.ElapsedTicks + " ticks";

      if (string.IsNullOrWhiteSpace(message))
        Trace.WriteLine("Elapsed time: " + time);
      else
        Trace.WriteLine(string.Format("{0} (Elapsed time: {1})", message, time));
    }