Convert a string to a date in C++

Question

I know this may be simple but being C++ I doubt it will be. How do I convert a string in the form 01/01/2008 to a date so I can manipulate it? I am happy to break the string into the day month year constituents. Also happy if solution is Windows only.

score 18 · Answer 1 · answered Nov 21 '08 at 10:46

18

#include <time.h>
char *strptime(const char *buf, const char *format, struct tm *tm);

answered Nov 21 '08 at 10:46

kenny

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score 9 · Answer 2 · edited Feb 17 '12 at 08:49

9

I figured it out without using strptime.

Break the date down into its components i.e. day, month, year, then:

struct tm  tm;
time_t rawtime;
time ( &rawtime );
tm = *localtime ( &rawtime );
tm.tm_year = year - 1900;
tm.tm_mon = month - 1;
tm.tm_mday = day;
mktime(&tm);

tm can now be converted to a time_t and be manipulated.

edited Feb 17 '12 at 08:49

bluish

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answered Nov 21 '08 at 14:24

Ubervan

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score 2 · Answer 3 · answered May 22 '14 at 05:56

For everybody who is looking for strptime() for Windows, it requires the source of the function itself to work. The latest NetBSD code does not port to Windows easily, unfortunately.

I myself have used the implementation here (strptime.h and strptime.c).

Another helpful piece of code can be found here. This comes originally from Google Codesearch, which does not exist anymore.

Hope this saves a lot of searching, as it took me quite a while to find this (and most often ended up at this question).

score 2 · Answer 4 · answered Nov 04 '14 at 15:45

#include <time.h>
#include <iostream>
#include <sstream>
#include <algorithm>

using namespace std;

int main ()
{
  time_t rawtime;
  struct tm * timeinfo;
  int year, month ,day;
  char str[256];

  cout << "Inter date: " << endl; 
  cin.getline(str,sizeof(str));

  replace( str, str+strlen(str), '/', ' ' );  
  istringstream( str ) >> day >> month >> year;

  time ( &rawtime );
  timeinfo = localtime ( &rawtime );
  timeinfo->tm_year = year - 1900;
  timeinfo->tm_mon = month - 1;
  timeinfo->tm_mday = day;
  mktime ( timeinfo );

  strftime ( str, sizeof(str), "%A", timeinfo );
  cout << str << endl;
  system("pause");
  return 0;
}

Works well.. With just a little modification this should be the best answer — Everyone, Jan 31 '17 at 08:36

score 2 · Answer 5 · answered Sep 17 '15 at 14:53

2

Why not go for a simpler solution using boost

using namespace boost::gregorian;
using namespace boost::posix_time;    
ptime pt = time_from_string("20150917");

answered Sep 17 '15 at 14:53

Johan Engblom

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score 1 · Answer 6 · answered Apr 23 '15 at 06:15

You can utilize the boost library(cross platform)

#include <stdio.h>
#include "boost/date_time/posix_time/posix_time.hpp"

int main()
{    
std::string strTime = "2007-04-11 06:18:29.000";
std::tm tmTime = boost::posix_time::to_tm(boost::posix_time::time_from_string(strTime));
return 0;
}

But the format should be as mentioned :)

Convert a string to a date in C++

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