QueryPerformanceFrequency Window下的高精度计时器

#include "stdafx.h"

#include <iostream>

#include <windows.h>

#include "AcquireExecutionTime.h"

int _tmain(int argc, _TCHAR* argv[])

{

AcquireExecutionTime apt;

if(apt.IsSupport() == false )

{

return -1;

}

for(int i=0; i< 10; i++)

{

Sleep(100);

std::cout << i << std::endl;

}

printf("%f milisecond\n", apt.GetTimeSpanMS(false));

for(int i=0; i< 10; i++)

{

Sleep(100);

std::cout << i << std::endl;

}

printf("%f milisecond\n", apt.GetTimeSpanMS(false));

return 0;

}

// .h#ifndef ACQUIRE_EXECUTION_TIME_H#ifndef ACQUIRE_EXECUTION_TIME_H#include <windows.h>class AcquireExecutionTime{public:AcquireExecutionTime(void);~AcquireExecutionTime(void);public:double GetTimeSpanSec(bool isReset = false);double GetTimeSpanMS(bool isReset = false){ return GetTimeSpanSec(isReset) * 1000; }BOOL IsSupport() const { return m_bSupport; }protected:BOOL Reset();private:BOOLm_bSupport;LARGE_INTEGERm_lFrequency;LARGE_INTEGERm_lStartTime;};#endif//.cpp#include "AcquireExecutionTime.h"AcquireExecutionTime::AcquireExecutionTime(void){this->Reset();}AcquireExecutionTime::~AcquireExecutionTime(void){}BOOL AcquireExecutionTime::Reset(){m_bSupport = QueryPerformanceFrequency(&m_lFrequency) == 0 ? FALSE : TRUE;if (m_bSupport){ return QueryPerformanceCounter(&m_lStartTime);}return FALSE;}double AcquireExecutionTime::GetTimeSpanSec(bool isReset){if (m_bSupport){LARGE_INTEGERendTime;QueryPerformanceCounter(&endTime);double ret = (double)(endTime.QuadPart - m_lStartTime.QuadPart)/(double)m_lFrequency.QuadPart;if(isReset){this->Reset();}return ret;}return -1;}