.NET中实现高精度定时器的思路

void Spin(Stopwatch w, int duration)
{
    var current = w.ElapsedMilliseconds;
    while ((w.ElapsedMilliseconds - current) < duration)
        Thread.SpinWait(5);
}

void wait(Stopwatch w, int duration)
{
    var current = w.ElapsedMilliseconds;
    while ((w.ElapsedMilliseconds - current) < duration)
        Thread.Sleep(0);
}

public enum TimerError
{
    MMSYSERR_NOERROR = 0,
    MMSYSERR_ERROR = 1,
    MMSYSERR_INVALPARAM = 11,
    MMSYSERR_NOCANDO = 97,
}
public enum RepeateType
{
    TIME_ONESHOT=0x0000,
    TIME_PERIODIC = 0x0001
}
public enum CallbackType
{
    TIME_CALLBACK_FUNCTION = 0x0000,
    TIME_CALLBACK_EVENT_SET = 0x0010,
    TIME_CALLBACK_EVENT_PULSE = 0x0020,
    TIME_KILL_SYNCHRONOUS = 0x0100
}
public class HighPrecisionTimer
{
    private delegate void TimerCallback(int id, int msg, int user, int param1, int param2);
    [DllImport("winmm.dll", EntryPoint = "timeGetDevCaps")]
    private static extern TimerError TimeGetDevCaps(ref TimerCaps ptc, int cbtc);
    [DllImport("winmm.dll", EntryPoint = "timeSetEvent")]
    private static extern int TimeSetEvent(int delay, int resolution, TimerCallback callback, int user, int eventType);
    [DllImport("winmm.dll", EntryPoint = "timeKillEvent")]
    private static extern TimerError TimeKillEvent(int id);
    private static TimerCaps _caps;
    private int _interval;
    private int _resolution;
    private TimerCallback _callback;
    private int _id;
    static HighPrecisionTimer()
    {
        TimeGetDevCaps(ref _caps, Marshal.SizeOf(_caps));
    }
    public HighPrecisionTimer()
    {
        Running = false;
        _interval = _caps.periodMin;
        _resolution = _caps.periodMin;
        _callback = new TimerCallback(TimerEventCallback);
    }
    ~HighPrecisionTimer()
    {
        TimeKillEvent(_id);
    }
    public int Interval
    {
        get { return _interval; }
        set
        {
            if (value < _caps.periodMin || value > _caps.periodMax)
                throw new Exception("invalid Interval");
            _interval = value;
        }
    }
    public bool Running { get; private set; }
    public event Action Ticked;
    public void Start()
    {
        if (!Running)
        {
            _id = TimeSetEvent(_interval, _resolution, _callback, 0,
                (int)RepeateType.TIME_PERIODIC | (int)CallbackType.TIME_KILL_SYNCHRONOUS);
            if (_id == 0) throw new Exception("failed to start Timer");
            Running = true;
        }
    }
    public void Stop()
    {
        if (Running)
        {
            TimeKillEvent(_id);
            Running = false;
        }
    }
    private void TimerEventCallback(int id, int msg, int user, int param1, int param2)
    {
        Ticked?.Invoke();
    }
}