你可以使用boost和chrono库:

#include <iostream>
#include <chrono>
#include <boost/date_time/posix_time/posix_time.hpp>

using boost::posix_time::to_iso_extended_string;
using boost::posix_time::from_time_t;
using std::chrono::system_clock;

int main()
{
  auto now = system_clock::now();
  std::cout << to_iso_extended_string(from_time_t(system_clock::to_time_t(now)));
}

std C库提供time()。 这是从纪元开始的秒数，可以使用标准C函数转换为日期和H:M:S。Boost还有一个时间/日期库供您检查。

time_t  timev;
time(&timev);

这为我在Linux (RHEL)和Windows (x64)上编译，目标是g++和OpenMP:

#include <ctime>
#include <iostream>
#include <string>
#include <locale>

////////////////////////////////////////////////////////////////////////////////
//
//  Reports a time-stamped update to the console; format is:
//       Name: Update: Year-Month-Day_of_Month Hour:Minute:Second
//
////////////////////////////////////////////////////////////////////////////////
//
//  [string] strName  :  name of the update object
//  [string] strUpdate:  update descripton
//          
////////////////////////////////////////////////////////////////////////////////

void ReportTimeStamp(string strName, string strUpdate)
{
    try
    {
        #ifdef _WIN64
            //  Current time
            const time_t tStart = time(0);
            //  Current time structure
            struct tm tmStart;

            localtime_s(&tmStart, &tStart);

            //  Report
            cout << strName << ": " << strUpdate << ": " << (1900 + tmStart.tm_year) << "-" << tmStart.tm_mon << "-" << tmStart.tm_mday << " " << tmStart.tm_hour << ":" << tmStart.tm_min << ":" << tmStart.tm_sec << "\n\n";
        #else
            //  Current time
            const time_t tStart = time(0);
            //  Current time structure
            struct tm* tmStart;

            tmStart = localtime(&tStart);

            //  Report
            cout << strName << ": " << strUpdate << ": " << (1900 + tmStart->tm_year) << "-" << tmStart->tm_mon << "-" << tmStart->tm_mday << " " << tmStart->tm_hour << ":" << tmStart->tm_min << ":" << tmStart->tm_sec << "\n\n";
        #endif

    }
    catch (exception ex)
    {
        cout << "ERROR [ReportTimeStamp] Exception Code:  " << ex.what() << "\n";
    }

    return;
}

你可以尝试下面的跨平台代码来获取当前的日期/时间:

#include <iostream>
#include <string>
#include <stdio.h>
#include <time.h>

// Get current date/time, format is YYYY-MM-DD.HH:mm:ss
const std::string currentDateTime() {
    time_t     now = time(0);
    struct tm  tstruct;
    char       buf[80];
    tstruct = *localtime(&now);
    // Visit http://en.cppreference.com/w/cpp/chrono/c/strftime
    // for more information about date/time format
    strftime(buf, sizeof(buf), "%Y-%m-%d.%X", &tstruct);

    return buf;
}

int main() {
    std::cout << "currentDateTime()=" << currentDateTime() << std::endl;
    getchar();  // wait for keyboard input
}

输出:

currentDateTime()=2012-05-06.21:47:59

有关日期/时间格式的更多信息，请访问这里

我发现这个链接对我的实现非常有用: c++日期和时间

下面是我在实现中使用的代码，以获得清晰的“YYYYMMDD HHMMSS”输出格式。参数in用于在UTC和本地时间之间切换。您可以轻松地修改我的代码以满足您的需要。

#include <iostream>
#include <ctime>

using namespace std;

/**
 * This function gets the current date time
 * @param useLocalTime true if want to use local time, default to false (UTC)
 * @return current datetime in the format of "YYYYMMDD HHMMSS"
 */

string getCurrentDateTime(bool useLocalTime) {
    stringstream currentDateTime;
    // current date/time based on current system
    time_t ttNow = time(0);
    tm * ptmNow;

    if (useLocalTime)
        ptmNow = localtime(&ttNow);
    else
        ptmNow = gmtime(&ttNow);

    currentDateTime << 1900 + ptmNow->tm_year;

    //month
    if (ptmNow->tm_mon < 9)
        //Fill in the leading 0 if less than 10
        currentDateTime << "0" << 1 + ptmNow->tm_mon;
    else
        currentDateTime << (1 + ptmNow->tm_mon);

    //day
    if (ptmNow->tm_mday < 10)
        currentDateTime << "0" << ptmNow->tm_mday << " ";
    else
        currentDateTime <<  ptmNow->tm_mday << " ";

    //hour
    if (ptmNow->tm_hour < 10)
        currentDateTime << "0" << ptmNow->tm_hour;
    else
        currentDateTime << ptmNow->tm_hour;

    //min
    if (ptmNow->tm_min < 10)
        currentDateTime << "0" << ptmNow->tm_min;
    else
        currentDateTime << ptmNow->tm_min;

    //sec
    if (ptmNow->tm_sec < 10)
        currentDateTime << "0" << ptmNow->tm_sec;
    else
        currentDateTime << ptmNow->tm_sec;


    return currentDateTime.str();
}

输出(UTC, EST):

20161123 000454
20161122 190454

你可以使用boost和chrono库:

#include <iostream>
#include <chrono>
#include <boost/date_time/posix_time/posix_time.hpp>

using boost::posix_time::to_iso_extended_string;
using boost::posix_time::from_time_t;
using std::chrono::system_clock;

int main()
{
  auto now = system_clock::now();
  std::cout << to_iso_extended_string(from_time_t(system_clock::to_time_t(now)));
}