在Windows系统下，需要延迟一定的时间后继续流程，貌似缺乏这种库函数，MFC提供的延迟函数似乎本质精度无法保证。比如Sleep。在下面提出一种方法，请大家斧正。当然先提出一点，有人认为在Windows系统先不可能获得准确定时，或者把系统挂起来延迟等待不符合多线程编程规范。是的，谢谢您的提醒，但这个讨论中大家就不要再重复这样的观点啦。我们的确需要精确定时，即使我把系统完全占用也在所不惜。不就是几十毫秒嘛 :)

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// 高精度延迟函数 【开发草稿】 Rev 0.01
/* 注：MSDN中提到的以下问题，本版本程序并未处理！！
On a multiprocessor computer, it should not matter which processor is called. 
However, you can get different results on different processors due to bugs 
in the basic input/output system (BIOS) or the hardware abstraction layer (HAL).
To specify processor affinity for a thread, use the SetThreadAffinityMask function. 
*/
int DelayPrecision(int TimeInMilliSecond)
{
    LARGE_INTEGER Frequency;
    LARGE_INTEGER CountBegin;
    LARGE_INTEGER CountNow;
    LONGLONG DelayCount;
    LONGLONG EndCount;
 
    if (0 != QueryPerformanceFrequency(&Frequency))
    {
        //试算终止计数
        DelayCount = Frequency.QuadPart / 1000 * TimeInMilliSecond;
        if (0 != QueryPerformanceCounter(&CountBegin))
        {
            EndCount = CountBegin.QuadPart + DelayCount;
            if (EndCount < CountBegin.QuadPart)
            {
                //计数器循环回去了
                while (1)
                {
                    if (0 != QueryPerformanceCounter(&CountNow))
                    {
                        if (CountNow.QuadPart < CountBegin.QuadPart && CountNow.QuadPart > EndCount)
                        {
                            return 1;
                        }
                    }
                    else
                    {
                        break;
                    }
                }
            }
            else
            {
                //一般情况
                while (1)
                {
                    if (0 != QueryPerformanceCounter(&CountNow))
                    {
                        if (CountNow.QuadPart > EndCount)
                        {
                            return 2;
                        }
                    }
                    else
                    {
                        break;
                    }
                }
            }
 
        }
 
    }
 
    //如果无法使用高精度定时器,拿Sleep凑合着用吧.
    Sleep(TimeInMilliSecond);
 
 
    return 0;
}