c++与C共享它的日期/时间函数。tm结构可能是c++程序员最容易使用的结构——下面打印今天的日期:

#include <ctime>
#include <iostream>

int main() {
    std::time_t t = std::time(0);   // get time now
    std::tm* now = std::localtime(&t);
    std::cout << (now->tm_year + 1900) << '-' 
         << (now->tm_mon + 1) << '-'
         <<  now->tm_mday
         << "\n";
}

从c++ 11开始，你可以使用std::chrono::system_clock::now()

示例(复制自en.cppreference.com):

#include <iostream>
#include <chrono>
#include <ctime>    

int main()
{
    auto start = std::chrono::system_clock::now();
    // Some computation here
    auto end = std::chrono::system_clock::now();
 
    std::chrono::duration<double> elapsed_seconds = end-start;
    std::time_t end_time = std::chrono::system_clock::to_time_t(end);
 
    std::cout << "finished computation at " << std::ctime(&end_time)
              << "elapsed time: " << elapsed_seconds.count() << "s"
              << std::endl;
}

这应该打印如下内容:

finished computation at Mon Oct  2 00:59:08 2017
elapsed time: 1.88232s

你也可以直接使用ctime():

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

int main ()
{
  time_t rawtime;
  struct tm * timeinfo;

  time ( &rawtime );
  printf ( "Current local time and date: %s", ctime (&rawtime) );

  return 0;
} 

ctime std::

为什么到目前为止只有评论提到了ctime ?

#include <ctime>
#include <iostream>
 
int main()
{
    std::time_t result = std::time(nullptr);
    std::cout << std::ctime(&result);
}

输出

周二 12月 27 5：21：29 PM 2011

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)));
}

#include <iostream>
#include <chrono>
#include <string>
#pragma warning(disable: 4996)
// Ver: C++ 17 
// IDE: Visual Studio
int main() {
    using namespace std; 
    using namespace chrono;
    time_point tp = system_clock::now();
    time_t tt = system_clock::to_time_t(tp);
    cout << "Current time: " << ctime(&tt) << endl;
    return 0;
}