c#微妙级计数器

 

Code
using System;
using System.Runtime.InteropServices;
using System.ComponentModel;
using System.Threading;


 internal class HiPerfTimer
  {
   [DllImport("Kernel32.dll")]
   private static extern bool QueryPerformanceCounter(
    out long lpPerformanceCount);

   [DllImport("Kernel32.dll")]
   private static extern bool QueryPerformanceFrequency(
    out long lpFrequency);

   private long startTime, stopTime;
   private long freq;

   // Constructor
   public HiPerfTimer()
   {
    startTime = 0;
    stopTime  = 0;

    if (QueryPerformanceFrequency(out freq) == false)
    {
     // high-performance counter not supported
     throw new Win32Exception();
    }
   }

   // Start the timer
   public void Start()
   {
    // lets do the waiting threads there work
    Thread.Sleep(0);

    QueryPerformanceCounter(out startTime);
   }

   // Stop the timer
   public void Stop()
   {
    QueryPerformanceCounter(out stopTime);
   }

   // Returns the duration of the timer (in seconds)
   public double Duration
   {
    get
    {
     return (double)(stopTime - startTime) / (double) freq;
    }
   }
  }

 } 

 

 

using System;
using System.Collections.Generic;
using System.Text;
 
using System.Runtime.InteropServices;   
using System.Threading;   
namespace ConsoleApplication1
{
    class Program
    {
        [DllImport("kernel32.dll")]
        private static extern bool QueryPerformanceFrequency(ref   Int64 lpFrequency);

        [DllImport("kernel32.dll")]
        private static extern bool QueryPerformanceCounter(ref   Int64 lpPerformanceCount);      

        public static void Main(string[] args)
        {
            //long time;
            //time = DateTime.Now.Ticks;
            //Console.WriteLine(time);
            long frequency = 0;
            if (!QueryPerformanceFrequency(ref   frequency))
            {
                Console.WriteLine("not   supported.");
                return;
            }
            long start = 0;
            if (!QueryPerformanceCounter(ref   start))
            {
                Console.WriteLine("query   start   failed.");
                return;
            }
            Thread.Sleep(1000);
            long end = 0;
            if (!QueryPerformanceCounter(ref   end))
            {
                Console.WriteLine("query   end   failed.");
                return;
            }
            Console.WriteLine("frequency   =   {0},   total   time   {1}",
                frequency, (double)(end - start) / ((double)frequency));   
            
  
        }
    }
}