ustime.h

bulkloop application source code based on mfc

/************************************************************
*	函数BOOL QueryPerformanceFrequency (LARGE_INTEGER ＊lpFrequency)；
*	函数BOOL QueryPerformanceCounter (LARGE_INTEGER ＊lpCount)；
*	的参数的数据类型LARGE_INTEGER的声明。
*	typedef union _LARGE_INTEGER
*	{
*　		struct{
*　　			DWORD LowPart ; // 4字节整型数
*　　			LONG　HighPart ; // 4字节整型数
*　			  };
*　		LONG QuadPart ; // 8字节整型数
*	} LARGE_INTEGER ;
************************************************************/
class usTime
{
public:
	usTime()
	{
		//取高精度运行计数器的频率，若硬件不支持则返回FALSE
		if( !QueryPerformanceFrequency( &frequence) )
			AfxMessageBox("Your computer hardware doesn't support the high-resolution performance counter");
	}
	/////////////////////////////////////////////////////////////////////////
	LONG MySleep(DWORD usNum )
	// 功能：执行实际的延时功能，Interval 参数为需要执行的延时与时间有关的数量，此函数返回执//行后实际所用的时间有关的数量 ；
	{
		LARGE_INTEGER sleepNUm, privious ,current, Elapse;
		//通过频率换算微秒数到对应的数量（与CPU时钟有关），1秒=1000000微秒；
		sleepNUm.QuadPart = frequence.QuadPart * usNum / 1000000;
		QueryPerformanceCounter( &privious );
		current = privious;
		while( current.QuadPart - privious.QuadPart < sleepNUm.QuadPart )
			QueryPerformanceCounter( &current );
		Elapse.QuadPart = current.QuadPart - privious.QuadPart;
		Elapse.QuadPart = LONG(1000000 * Elapse.QuadPart / frequence.QuadPart ); //换算到微秒数；
		return Elapse.QuadPart;
	}
	LONG WaitNTus(DWORD usNum , LARGE_INTEGER privious)
	// 功能：执行实际的延时功能，Interval 参数为需要执行的延时与时间有关的数量，此函数返回执//行后实际所用的时间有关的数量 ；
	{
		LARGE_INTEGER sleepNUm, current, Elapse;
		//通过频率换算微秒数到对应的数量（与CPU时钟有关），1秒=1000000微秒；
		sleepNUm.QuadPart = frequence.QuadPart * usNum / 1000000;
		//QueryPerformanceCounter( &privious );
		current = privious;
		while( current.QuadPart - privious.QuadPart < sleepNUm.QuadPart )
			QueryPerformanceCounter( &current );
		Elapse.QuadPart = current.QuadPart - privious.QuadPart;
		Elapse.QuadPart = LONG(1000000 * Elapse.QuadPart / frequence.QuadPart ); //换算到微秒数；
		return Elapse.QuadPart;
	}
private:
	LARGE_INTEGER frequence;
};