C_C++ 各种计时函数

对Windows平台下常用的计时函数进行总结，包括精度为秒、毫秒、微秒三种精度的5 种方法。分为在标准C/C++下的二种time()及clock()，标准C/C++所以使用的time()及clock()不仅可以用在Windows 系统，也可以用于Linux系统。

在Windows系统下三种，使用Windows提供的API接口timeGetTime()、 GetTickCount()及QueryPerformanceCounter()来完成。

[cpp]
#include <windows.h>
#include <time.h> //time_t time() clock_t clock()
#include <Mmsystem.h>             //timeGetTime()
#pragma comment(lib, "Winmm.lib")   //timeGetTime()

int main(int argc, char* argv[])
{
    //用time()来计时秒
    time_t timeBegin, timeEnd;
    timeBegin = time(NULL);
    Sleep(800);
    timeEnd = time(NULL);
    printf("time %d\n", timeEnd - timeBegin);


    //用clock()来计时毫秒
    clock_t clockBegin, clockEnd;
    clockBegin = clock();
    Sleep(800);
    clockEnd = clock();
    printf("clock %d\n", clockEnd - clockBegin);


    //用timeGetTime()来计时毫秒
    DWORD dwBegin, dwEnd;
    dwBegin = timeGetTime();
    Sleep(800);
    dwEnd = timeGetTime();
    printf("timeGetTime %d\n", dwEnd - dwBegin);


    //用GetTickCount()来计时毫秒
    DWORD dwGTCBegin, dwGTCEnd;
    dwGTCBegin = GetTickCount();
    Sleep(800);
    dwGTCEnd = GetTickCount();
    printf("GetTickCount %d\n", dwGTCEnd - dwGTCBegin);


    //用QueryPerformanceCounter()来计时微秒
    LARGE_INTEGER large_interger;
    double dff;
    __int64 c1, c2;
    //获取是否支持精确定时器。定时器的频率
    if( QueryPerformanceFrequency(&large_interger) )
    {
        dff = large_interger.QuadPart;
        //获取定时器的值
        QueryPerformanceCounter(&large_interger);
        c1 = large_interger.QuadPart;
        Sleep(800);
        //获取定时器的值
        QueryPerformanceCounter(&large_interger);
        c2 = large_interger.QuadPart;
        printf("本机高精度计时器频率%lf\n", dff);
        printf("第一次计时器值%I64d 第二次计时器值%I64d 计时器差%I64d\n", c1, c2, c2 - c1);
        printf("计时%lf毫秒\n", (c2 - c1) * 1000 / dff);
        printf("\n");
    }

    return 0;
}

#include <windows.h>
#include <time.h> //time_t time() clock_t clock()
#include <Mmsystem.h> //timeGetTime()
#pragma comment(lib, "Winmm.lib") //timeGetTime()

int main(int argc, char* argv[])
{
    //用time()来计时秒
    time_t timeBegin, timeEnd;
    timeBegin = time(NULL);
    Sleep(800);
    timeEnd = time(NULL);
    printf("time %d\n", timeEnd - timeBegin);


    //用clock()来计时毫秒
    clock_t clockBegin, clockEnd;
    clockBegin = clock();
    Sleep(800);
    clockEnd = clock();
    printf("clock %d\n", clockEnd - clockBegin);


    //用timeGetTime()来计时毫秒
    DWORD dwBegin, dwEnd;
    dwBegin = timeGetTime();
    Sleep(800);
    dwEnd = timeGetTime();
    printf("timeGetTime %d\n", dwEnd - dwBegin);


    //用GetTickCount()来计时毫秒
    DWORD dwGTCBegin, dwGTCEnd;
    dwGTCBegin = GetTickCount();
    Sleep(800);
    dwGTCEnd = GetTickCount();
    printf("GetTickCount %d\n", dwGTCEnd - dwGTCBegin);


    //用QueryPerformanceCounter()来计时微秒
    LARGE_INTEGER large_interger;
    double dff;
    __int64 c1, c2;
    //获取是否支持精确定时器。定时器的频率
    if( QueryPerformanceFrequency(&large_interger) )
    {
        dff = large_interger.QuadPart;
        //获取定时器的值
        QueryPerformanceCounter(&large_interger);
        c1 = large_interger.QuadPart;
        Sleep(800);
        //获取定时器的值
        QueryPerformanceCounter(&large_interger);
        c2 = large_interger.QuadPart;
        printf("本机高精度计时器频率%lf\n", dff);

补充：软件开发 , C++ ,