How do you convert Stopwatch ticks to nanoseconds, milliseconds and seconds?

Question

This is a very basic question...quite embarassing, but here goes:

I have a Stopwatch block in C# code. I determine the elapsed time in ticks and then want to convert to ns, ms, s. I know that the Frequency is provided by the Stopwatch class and that it is required for conversion.

Thanks

Answer 1

Stopwatch.Elapsed is a TimeSpan, so you can do myStopwatch.Elapsed.TotalMilliseconds, myStopwatch.Elapsed.TotalSeconds, etc.

// Create new stopwatch Stopwatch stopwatch = new Stopwatch();  // Begin timing stopwatch.Start();  // Do something for (int i = 0; i < 1000; i++) {     Thread.Sleep(1); }  // Stop timing stopwatch.Stop();  // Write result Console.WriteLine("Time elapsed (s): {0}", stopwatch.Elapsed.TotalSeconds); Console.WriteLine("Time elapsed (ms): {0}", stopwatch.Elapsed.TotalMilliseconds); Console.WriteLine("Time elapsed (ns): {0}", stopwatch.Elapsed.TotalMilliseconds * 1000000); 

Output:

Time elapsed (s): 2.4976622 Time elapsed (ms): 2497.6622 Time elapsed (ns): 2497662200 

Note that stopwatch.ElapsedMilliseconds returns a long and is thus only precise up to the millisecond, while stopwatch.Elapsed.TotalMilliseconds returns a double and has the same precision as stopwatch.ElapsedTicks, except it's easier to use. ILSpy shows that TimeSpan.TotalMilliseconds is computed using ticks anyway.

Answer 2

According to MSDN, Frequency tells you the number of ticks per second. Therefore:

Stopwatch sw = new Stopwatch(); // ... double ticks = sw.ElapsedTicks; double seconds = ticks / Stopwatch.Frequency; double milliseconds = (ticks / Stopwatch.Frequency) * 1000; double nanoseconds = (ticks / Stopwatch.Frequency) * 1000000000;