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| Member functions | ||||
time_get::get_monthnametime_get::do_get_monthname | ||||
Defined in header <locale> | ||
public: iter_type get_monthname( iter_type beg, iter_type end,std::ios_base& str, | (1) | |
protected: virtual iter_type do_get_monthname( iter_type beg, iter_type end,std::ios_base& str, | (2) | |
do_get_monthname of the most derived class.[beg, end) and parses out the month name (possibly abbreviated), using the default format for month names expected by this locale, which is the same format as"%b" as used by the functionsstd::get_time,time_get::get, and the POSIX functionstrptime().If it finds abbreviated name, followed by the characters that are valid for the full name, it continues reading until it consumes all the characters for the full name or finds a character that isn't expected, in which case parsing fails even if the first few characters were a valid abbreviation.
The parsed month is stored in thestd::tm fieldt->tm_mon.
If the end iterator is reached before a valid month name is read, the function setsstd::ios_base::eofbit inerr. If a parsing error is encountered, the function setsstd::ios_base::failbit inerr.
Contents |
| beg | - | iterator designating the start of the sequence to parse |
| end | - | one past the end iterator for the sequence to parse |
| str | - | a stream object that this function uses to obtain locale facets when needed, e.g.std::ctype to skip whitespace orstd::collate to compare strings |
| err | - | stream error flags object that is modified by this function to indicate errors |
| t | - | pointer to thestd::tm object that will hold the result of this function call |
Iterator pointing one past the last character in[beg, end) that was recognized as a part of a valid month name.
This function is usually case-insensitive.
If a parsing error is encountered, most implementations of this function leave*t unmodified.
#include <ctime>#include <iostream>#include <iterator>#include <locale>#include <sstream>#include <string_view> void try_get_mon(std::string_view locale_name,std::string_view source){try{std::locale::global(std::locale(locale_name.data()));}catch(std::runtime_errorconst& ex){std::cout<<"Cannot setup locale: "<< locale_name<<"\n""Exception: "<< ex.what()<<'\n';return;} std::cout<<"Parsing the month out of '"<< source<<"' in the locale "<<std::locale().name()<<'\n';std::istringstream str{source.data()};std::ios_base::iostate err=std::ios_base::goodbit; std::tm t;std::time_get<char>const& facet=std::use_facet<std::time_get<char>>(str.getloc());std::istreambuf_iterator<char> ret= facet.get_monthname({str},{}, str, err,&t); str.setstate(err);std::istreambuf_iterator<char> last{}; if(str){std::cout<<"Successfully parsed, month number is "<< t.tm_mon; if(ret!= last){std::cout<<". Remaining content: ";std::copy(ret, last,std::ostreambuf_iterator<char>(std::cout));}elsestd::cout<<". The input was fully consumed";}else{std::cout<<"Parse failed. Unparsed string: ";std::copy(ret, last,std::ostreambuf_iterator<char>(std::cout));} std::cout<<'\n';} int main(){ try_get_mon("ja_JP.utf8","2月"); try_get_mon("th_TH.utf8","กุมภาพันธ์"); try_get_mon("el_GR.utf8","Φεβ"); try_get_mon("el_GR.utf8","Φεβρουάριος"); try_get_mon("en_US.utf8","Febrile");}
Possible output:
Parsing the month out of '2月' in the locale ja_JP.utf8Successfully parsed, month number is 1. The input was fully consumedParsing the month out of 'กุมภาพันธ์' in the locale th_TH.utf8Successfully parsed, month number is 1. The input was fully consumedParsing the month out of 'Φεβ' in the locale el_GR.utf8Successfully parsed, month number is 1. The input was fully consumedParsing the month out of 'Φεβρουάριος' in the locale el_GR.utf8Successfully parsed, month number is 1. The input was fully consumedParsing the month out of 'Febrile' in the locale en_US.utf8Parse failed. Unparsed string: ile
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior |
|---|---|---|---|
| LWG 248 | C++98 | eofbit was not set upon reaching the end iterator | setseofbit if a valid month name has not been read |
(C++11) | parses a date/time value of specified format (function template)[edit] |
