Question

我需要从计时器

获得毫秒

    // get timer part
    time_t timer = time(NULL);
    struct tm now = *localtime( &timer );
    char timestamp[256];

    // format date time
    strftime(timestamp, sizeof(timestamp), "%Y-%m-%d_%H.%M.%S", &now);

我希望在C＃中得到这样的结果：

DateTime.Now.ToString("yyyy-MM-dd_HH.mm.ss.ff")

我尝试使用％f或％F，但它确实适用于C ++。如何从tm获得％f的毫秒数？

提前致谢

Answer 1

#include <chrono>

typedef std::chrono::system_clock Clock;

auto now = Clock::now();
auto seconds = std::chrono::time_point_cast<std::chrono::seconds>(now);
auto fraction = now - seconds;
time_t cnow = Clock::to_time_t(now);

然后你可以用秒精度打印出time_t，然后打印分数代表的任何内容。可能是毫秒，微秒或其他东西。要专门获得毫秒：

auto milliseconds = std::chrono::duration_cast<std::chrono::milliseconds>(fraction);
std::cout << milliseconds.count() << '\n';

Answer 2

在使用Win32 API的Windows上 SYSTEMTIME structure会给你几毫秒。然后，您应该使用Time Functions来获取时间。像这样：

#include <windows.h>

int main()
{
    SYSTEMTIME stime;
    //structure to store system time (in usual time format)
    FILETIME ltime;
    //structure to store local time (local time in 64 bits)
    FILETIME ftTimeStamp;
    char TimeStamp[256];//to store TimeStamp information
    GetSystemTimeAsFileTime(&ftTimeStamp); //Gets the current system time

    FileTimeToLocalFileTime (&ftTimeStamp,&ltime);//convert in local time and store in ltime
    FileTimeToSystemTime(&ltime,&stime);//convert in system time and store in stime

    sprintf(TimeStamp, "%d:%d:%d:%d, %d.%d.%d",stime.wHour,stime.wMinute,stime.wSecond, 
            stime.wMilliseconds, stime.wDay,stime.wMonth,stime.wYear);

    printf(TimeStamp);

    return 0;
}

Answer 3

有getimeofday（）函数。以ms为单位返回时间点击此处：http://souptonuts.sourceforge.net/code/gettimeofday.c.html

Answer 4

这是另一个c ++ 11答案：

Answer 5

你可以选择boost::posix_time::ptime课程。它的reference there。

Answer 6

我个人使用这个：http://wyw.dcweb.cn/time.htm

Answer 7

在MS Visual Studio下，c / c ++包含sys / timeb.h并使用_ftime（_ftime_s）。检索包含time_t结构和毫秒的struct _timeb（_ftime64），请参阅MSDN customerAddressUpdate

#include <sys/timeb.h>

struct _timeb timebuffer;
_ftime(&timebuffer);
timebuffer.millitm; //milli seconds
timebuffer.time; //the same like struct time_t

Answer 8

尝试使用此代码：

struct tvTime;

gettimeofday(&tvTime, NULL);

int iTotal_seconds = tvTime.tv_sec;
struct tm *ptm = localtime((const time_t *) & iTotal_seconds);

int iHour = ptm->tm_hour;;
int iMinute = ptm->tm_min;
int iSecond = ptm->tm_sec;
int iMilliSec = tvTime.tv_usec / 1000;
int iMicroSec = tvTime.tv_usec;

得到毫秒的时间

8 个答案: