如何在windows下面实现小于1毫秒的精确计时

如何在windows下面实现小于1毫秒的精确计时?请指教 问题点数：50、回复次数：6Top

1 楼z_sky（）回复于 2002-05-24 15:56:15 得分 10

Multimedia   Timer   Functions  
  The   following   functions   are   used   with   multimedia   timers.  
     
  timeBeginPeriod      
  timeEndPeriod      
  timeGetDevCaps      
  timeGetSystemTime      
  timeGetTime      
  timeKillEvent      
  TimeProc      
  timeSetEvent      
   
  check   them   with   MSDNTop

2 楼masterz（www.fruitfruit.com）回复于 2002-05-24 16:41:07 得分 10

__int64   RDTSC()  
   
  {  
   
  unsigned   int   lopart,   hipart;  
   
  __asm  
   
  {  
   
  rdtsc  
   
  mov   lopart,   eax  
   
  mov   hipart,   edx  
   
  }  
   
  return   lopart   +   (hipart*(4294967296UL));  
   
  }  
  Top

3 楼dylanwolf（）回复于 2002-05-24 16:48:51 得分 10

Use   this   two   functions,   can   achieve   微秒级别  
   
   
  QueryPerformanceCounter  
  The   QueryPerformanceCounter   function   retrieves   the   current   value   of   the   high-resolution   performance   counter,   if   one   exists.    
   
  QueryPerformanceFrequency  
  The   QueryPerformanceFrequency   function   retrieves   the   frequency   of   the   high-resolution   performance   counter,   if   one   exists.    
   
  BOOL   QueryPerformanceFrequency(  
      LARGE_INTEGER   *lpFrequency       //   address   of   current   frequency  
  );  
     
  Parameters  
  lpFrequency    
  Pointer   to   a   variable   that   the   function   sets,   in   counts   per   second,   to   the   current   performance-counter   frequency.   If   the   installed   hardware   does   not   support   a   high-resolution   performance   counter,   this   parameter   can   be   to   zero.    
   
   
  BOOL   QueryPerformanceCounter(  
      LARGE_INTEGER   *lpPerformanceCount       //   pointer   to   counter   value  
  );  
     
  Parameters  
  lpPerformanceCount    
  Pointer   to   a   variable   that   the   function   sets,   in   counts,   to   the   current   performance-counter   value.   If   the   installed   hardware   does   not   support   a   high-resolution   performance   counter,   this   parameter   can   be   to   zero.    
  Top

4 楼winne_ll（feiyang）回复于 2002-05-24 16:54:36 得分 20

可以精确到0.000001秒  
   
  看看下面的代码，你在VC里运行试试:)  
   
  #include   "stdafx.h"  
  #include   "windows.h"  
  int   main(int   argc,   char*   argv[])  
  {  
  LARGE_INTEGER   countstart;  
  LARGE_INTEGER   countend;  
  __int64   timediff;  
  LARGE_INTEGER   frequent;  
  QueryPerformanceCounter(   &countstart);  
  printf("Hello   World!\n");  
  printf("Hello   World!\n");  
  printf("Hello   World!\n");  
  QueryPerformanceCounter(   &countend);  
  timediff   =   (__int64)countend.QuadPart-(__int64)countstart.QuadPart;  
  QueryPerformanceFrequency(&frequent);  
  double   dsec   =   (double)timediff/(double)frequent.QuadPart;  
  printf("elapsed   time   :%f(second)\n",dsec);  
  return   0;  
  }  
  也可以用下面的  
      可以使用多媒体定时器啊，函数如下：  
  1。QueryPerformanceFrequency，取得你的系统支持的定时器的频率  
  2。QueryPerformanceCounter   ，计算走过的时间用，这个时间指的是系统启动后经历的时间，你自己程序的时间要用减法来算。Top

5 楼1980xls（狮子山人）回复于 2002-05-24 19:57:44 得分 0

getthinckcount()Top

6 楼programcat2001（旧游以梦）回复于 2002-05-24 19:58:53 得分 0

用工业计时器Top

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