C# 精准计时之QueryPerformanceCounterQueryPerformanceFrequency用法

C# 用法：

public static class QueryPerformanceMethd { [DllImport("kernel32.dll")] public extern static short QueryPerformanceCounter(ref long x); [DllImport("kernel32.dll")] public extern static short QueryPerformanceFrequency(ref long x); }

 

static void Main(string[] args) { long stop_Value = 0; long start_Value = 0; long freq = 0; QueryPerformanceMethd.QueryPerformanceFrequency(ref freq); QueryPerformanceMethd.QueryPerformanceCounter(ref start_Value); //Fun() 需要计时方法 QueryPerformanceMethd.QueryPerformanceCounter(ref stop_Value); double time = (double)(stop_Value - start_Value) / (double)(freq); Console.WriteLine(time);//单位S Console.ReadLine(); }

计算所得time即为fun（）方法所消耗时间。

 

 

C++中QueryPerformanceCounter  QueryPerformanceFrequency的用法

#include "stdafx.h" #include "windows.h" void main() { LARGE_INTEGER nFreq; LARGE_INTEGER nBeginTime; LARGE_INTEGER nEndTime; double time; QueryPerformanceFrequency(&nFreq); QueryPerformanceCounter(&nBeginTime); Sleep(1000); QueryPerformanceCounter(&nEndTime); time = (double)(nEndTime.QuadPart - nBeginTime.QuadPart) / (double)nFreq.QuadPart; printf("%f\n", time); system("Pause"); }

计算Sleep（1000）所消耗的精确时间，并非精确的1s

 

转载于:https://www.cnblogs.com/Van-Bumblebee/p/5483432.html