Stopwatch get a more accurate running time

In the past, we often saw a bunch of people discussing a method better, saving time.
Later, someone suggested that the time precision obtained by using datetime. Now is not enough.

Msdn
See
There is
Stopwatch Method

In a typical stopwatch solution, call the start method, call the stop method, and use the elapsed attribute to check the running time.
By default, the running time value of the stopwatch instance is equivalent to the sum of all measured intervals. The cumulative running time count starts when start is called each time. The current interval measurement ends when stop is called each time, and the cumulative running time value is frozen. You can use the reset method to clear the accumulated running time of an existing stopwatch instance.