std::time_get::date_order, std::time_get::do_date_order

 

C++

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Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

 

Localizations library

Locales and facets
locale
use_facet	has_facet
Character classification
isspace isblank (C++11) iscntrl isupper islower isalpha	isdigit ispunct isxdigit isalnum isprint isgraph
Conversions
toupper tolower	wstring_convert (C++11) wbuffer_convert (C++11)
Facet category base classes
ctype_base codecvt_base messages_base	time_base money_base
Facet categories
ctype ctype<char> codecvt collate messages time_get time_put	num_get num_put numpunct money_get money_put moneypunct
Locale-specific facets
ctype_byname codecvt_byname messages_byname collate_byname	time_get_byname time_put_byname numpunct_byname moneypunct_byname
Code conversion facets
codecvt_utf8 (C++11) codecvt_utf16 (C++11)	codecvt_utf8_utf16 (C++11) codecvt_mode (C++11)
C locale
setlocale localeconv lconv	LC_ALLLC_COLLATELC_CTYPELC_MONETARYLC_NUMERICLC_TIME

 

std::time_get

Member functions

time_get::time_get

time_get::~time_get

time_get::date_ordertime_get::do_date_order

time_get::get_timetime_get::do_get_time

time_get::get_datetime_get::do_get_date

time_get::get_weekdaytime_get::do_get_weekday

time_get::get_monthnametime_get::do_get_monthname

time_get::get_yeartime_get::do_get_year

time_get::gettime_get::do_get

 

Defined in header <locale>
public: dateorder date_order() const;	(1)
protected: virtual dateorder do_date_order() const;	(2)

1) Public member function, calls the protected virtual member function do_date_order of the most derived class.

2) Returns a value of type std::time_base::dateorder, which describes the default date format used by this locale (expected by get_date() and produced by std::strftime() with format specifier '%x').

The valid values (inherited from std::time_base) are:

no_order	the format contains variable items (week day, Julian day, etc), or this function is not implemented
dmy	day, month, year (European locales)
mdy	month, day, year (American locales)
ymd	year, month, day (Asian locales)
ydm	year, day, month (rare)

Parameters

(none)

Return value

A value of type dateorder

Notes

This function is optional, it may return no_order in every case.

Example

Run this code

#include <iostream>
#include <locale>
 
void show_date_order()
{
    std::time_base::dateorder d = std::use_facet<std::time_get<char>>(
                                           std::locale()
                                  ).date_order();
    switch (d)
    {
        case std::time_base::no_order: std::cout << "no_order\n"; break;
        case std::time_base::dmy: std::cout << "day, month, year\n"; break;
        case std::time_base::mdy: std::cout << "month, day, year\n"; break;
        case std::time_base::ymd: std::cout << "year, month, day\n"; break;
        case std::time_base::ydm: std::cout << "year, day, month\n"; break;
    }
}
 
int main()
{
    std::locale::global(std::locale("en_US.utf8"));
    std::cout << "In U.S. locale, the default date order is: ";
    show_date_order();
 
    std::locale::global(std::locale("ja_JP.utf8"));
    std::cout << "In Japanese locale, the default date order is: ";
    show_date_order();
 
    std::locale::global(std::locale("de_DE.utf8"));
    std::cout << "In German locale, the default date order is: ";
    show_date_order();
}

Output:

In U.S. locale, the default date order is: month, day, year
In Japanese locale, the default date order is: year, month, day
In German locale, the default date order is: day, month, year

See also

do_get_date [virtual]	extracts month, day, and year from input stream (virtual protected member function)
time_base	defines date format constants (class)