std::time_get<CharT,InputIt>::get_time, std::time_get<CharT,InputIt>::do_get_time
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std::time_get
Member functions
time_get::get_timetime_get::do_get_time
Defined in header
<locale>
public:
(1)
iter_type get_time( iter_type beg, iter_type end, std::ios_base & str,
protected:
(2)
virtual iter_type do_get_time( iter_type beg, iter_type end, std::ios_base & str,
1) Public member function, calls the protected virtual member function
do_get_time of the most derived class.2) Reads successive characters from the sequence
[beg, end) and parses out the time value following the same rules as the format specifier "%H:%M:%S" as used by the functions std::get_time , time_get::get, and the POSIX function strptime().- The parsed time is stored in the corresponding fields of the std::tm structure pointed to by the argument t.
- If the end iterator is reached before a valid time is read, the function sets std::ios_base::eofbit in err. If a parsing error is encountered, the function sets std::ios_base::failbit in err.
[edit] Parameters
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
err
-
stream error flags object that is modified by this function to indicate errors
t
-
pointer to the std::tm object that will hold the result of this function call
[edit] Return value
Iterator pointing one past the last character in [beg, end) that was recognized as a part of a valid date.
[edit] Notes
For the alphabetic components of the default time format (if any), this function is usually case-insensitive.
If a parsing error is encountered, most implementations of this function leave *t unmodified.
[edit] Example
Run this code
#include <iostream> #include <iterator> #include <locale> #include <sstream> void try_get_time(const std::string & s) { std::cout << "Parsing the time out of '" << s << "' in the locale " << std::locale ().name() << '\n'; std::istringstream str(s); 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_time({str}, {}, str, err, &t); str.setstate(err); if (str) { std::cout << "Hours: " << t.tm_hour << ", " "Minutes: " << t.tm_min << ", " "Seconds: " << t.tm_sec << '\n'; } else { std::cout << "Parse failed. Unparsed string: "; std::copy (ret, {}, std::ostreambuf_iterator <char>(std::cout )); std::cout << '\n'; } } int main() { std::locale::global (std::locale ("ru_RU.utf8")); try_get_time("21:40:11"); try_get_time("21-40-11"); std::locale::global (std::locale ("ja_JP.utf8")); try_get_time("21時37分58秒"); }
Output:
Parsing the time out of '21:40:11' in the locale ru_RU.utf8 Hours: 21, Minutes: 40, Seconds: 11 Parsing the time out of '21-40-11' in the locale ru_RU.utf8 Parse failed. Unparsed string: -40-11 Parsing the time out of '21時37分58秒' in the locale ja_JP.utf8 Hours: 21, Minutes: 37, Seconds: 58
[edit] Defect reports
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
|
sets eofbit if a valid time has not been read
|
| LWG 461 | C++98 | do_get_time needed to parse localized time representation
|
parses with "%H:%M:%S" format |