Question

我正在使用C ++编写与时序相关的代码。

FILETIME ftTime;
GetSystemTimeAsFileTime(&ftTime);

struct DateTime
{
    unsigned int dwLowDateTime;
    unsigned int dwHighDateTime;
};



DateTime myTime;
myTime.dwHighDateTime = (unsigned int)ftTime.dwHighDateTime;
myTime.dwLowDateTime  = (unsigned int)ftTime.dwLowDateTime;

ussigned __int64 AsUInt64_t

unsigned __int64 myInt64Time = *(unsigned __int64*)&myTime;

// I have Getstring format from date time some thing like this below

Format() {

SYSTEMTIME  systemTime;
FileTimeToSystemTime(&fileTime, &systemTime);

const char*         formatString = "%04d-%02d-%02d %02d:%02d:%02d.%03d";

// I have few variable declartions to be used for snprintf which is not mentioned here.

apiResult = _snprintf_s(pBuffer, sizeOfBuffer, count, formatString, systemTime.wYear, systemTime.wMonth, systemTime.wDay, systemTime.wHour, systemTime.wMinute,                         systemTime.wSecond, systemTime.wMilliseconds);

}

DateTime startTime = now(); // some how I am getting latest time here.
sleep(5s); // sleeping for 5 seconds.
DateTime endTime = now(); // i.e., after 5 seconds.

std::cout << "\nOn Start Time:" << startTime.Format() << std::endl;
std::cout << "On End Tme:    " << endTime.Format() << std::endl;

std::cout << "On Start Read " << *(unsigned __int64*)&startTime << std::endl;
std::cout << "On End Read " << *(unsigned __int64*)&endtime<< std::endl;

///////////////////

以上输出如下：

On Start Time:2012-06-18 09:45:03.180
On End Time  :2012-06-18 09:45:08.183

// Int Int64 I am getting as below

On Start Read : 129844863031802858
On End Read   : 129844863081832935

我的问题是我想根据给定的间隔将边界划分为相等的间隔，例如每个间隔为2秒。我该怎么做？

天花板（范围/间隔）间隔。

例如，开始时间：12：00：00：0000，结束时间为12：01：52：00099。间隔是16秒，然后我们有7个间隔。

unsigned __int64 interval =16;

如果我(*(unsigned __int64*)&endtime - *(unsigned __int64*)&startTime) / interval)，如果我在逻辑上方使用int，那么我没有得到7？我该如何解决？

Answer 1

FILETIME struct包含一个64位值，表示自1601年1月1日（UTC）以来100纳秒间隔的数量。

点击此链接：FILETIME structure

因此，对两个FILETIME变量进行减法可以得出纳秒（nS）的时差。

将此除以16（秒）将无法满足您的需求。

除以16 * 10 ^ 9或使用为您执行此数学运算的difftime API (Link)，并以秒为单位返回时差。

在C ++中进行int64时间计算

1 个答案: