想得到一段程序的运行时间，C#中提供的time精确度太低，有没有精度比较高的算法？

Question

100ns为单位的数据还低？！
你去查查哪个的Api可以提供更高的
java还只有ms呢。

Answer 1

调用API QueryPerformanceCounter，QueryPerformanceFrequency可以实现，具体看看后面短代码。using System;
using System.Runtime.InteropServices;
using System.ComponentModel;
using System.Threading;namespace Win32
{
    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;

public HiPerfTimer()
{
            startTime = 0;
            stopTime  = 0;            if (QueryPerformanceFrequency(out freq) == false)
            {
                // 不支持高精度计时
                throw new Win32Exception(); 
            }
}

// 计时开始
public void Start()
{
            Thread.Sleep(0);   QueryPerformanceCounter(out startTime);
}

// 计时结束
public void Stop()
{
    QueryPerformanceCounter(out stopTime);
}

// 持续时间，单位秒
        public double Duration
        {
         get
         {
             return (double)(stopTime - startTime) / (double) freq;
            }
        } public static void Main()
{ HiPerfTimer pt = new HiPerfTimer();                    
pt.Start();                                            
Console.WriteLine("简单代码来测试高精度计时器\n");                           
pt.Stop();                                             
Console.WriteLine("持续时间: {0} sec\n", pt.Duration);  Console.ReadLine();
}
}
}