<PackageReference Include="NETStandard.Library" Version="2.0.0" />

System.Diagnostics.Stopwatch

public class Stopwatch
namespace System.Diagnostics { public class Stopwatch { public static readonly long Frequency; public static readonly bool IsHighResolution; public TimeSpan Elapsed { get; } public long ElapsedMilliseconds { get; } public long ElapsedTicks { get; } public bool IsRunning { get; } public Stopwatch(); public static long GetTimestamp(); public void Reset(); public void Restart(); public void Start(); public static Stopwatch StartNew(); public void Stop(); } }