HiPerfTimer.cs

namespace GenXdev.Additional.HiPerfTimer
{
    public class NativeMethods
    {
        [System.Runtime.InteropServices.DllImport("Kernel32.dll")]
        [System.Security.SuppressUnmanagedCodeSecurity()]
        private static extern bool QueryPerformanceCounter(out long lpPerformanceCount);
        [System.Runtime.InteropServices.DllImport("Kernel32.dll")]
        [System.Security.SuppressUnmanagedCodeSecurity()]
        private static extern bool QueryPerformanceFrequency(out long lpFrequency);
        private long startTime;
        private long stopTime;
        public bool stopped = true;
        private long freq;
 
        public NativeMethods(bool StartNow = false)
        {
            Interlocked.Exchange(ref startTime, 0);
            Interlocked.Exchange(ref stopTime, 0);
            freq = 0;
            if (QueryPerformanceFrequency(out freq) == false)
            {
                throw new Exception("Timer not supported");
            }
            if (StartNow)
                Start();
        }
 
        /// <summary>
        /// Start the timer
        /// </summary>
        /// <returns>long - tick count</returns>
        public long Start()
        {
            stopped = false;
            //startTime2 = DateTime.Now;
            QueryPerformanceCounter(out long startTimeTmp);
            Interlocked.Exchange(ref startTime, startTimeTmp);
            return startTimeTmp;
        }
 
        /// <summary>
        /// Stop timer
        /// </summary>
        /// <returns>long - tick count</returns>
        public long Stop()
        {
            stopped = true;
            //stopTime2 = DateTime.Now;
            QueryPerformanceCounter(out long stopTimeTmp);
            Interlocked.Exchange(ref stopTime, stopTimeTmp);
            return stopTimeTmp;
        }
 
        /// <summary>
        /// Return the duration of the timer (in seconds)
        /// </summary>
        /// <returns>double - duration</returns>
        public double Duration
        {
            get
            {
                if (stopped)
                {
                    return Convert.ToDouble(Interlocked.Read(ref stopTime) - Interlocked.Read(ref startTime)) / freq;
                }
                QueryPerformanceCounter(out long now);
                return Convert.ToDouble(now - Interlocked.Read(ref startTime)) / freq;
            }
        }
 
        /// <summary>
        /// Frequency of timer (no counts in one second on this machine)
        /// </summary>
        ///<returns>long - Frequency</returns>
        public long Frequency
        {
            get
            {
                return freq;
            }
        }
 
        public void Reset()
        {
            QueryPerformanceCounter(out long now);
            Interlocked.Exchange(ref startTime, now);
        }
    }
}