std::chrono::year_month_weekday::year, std::chrono::year_month_weekday::month, std::chrono::year_month_weekday::weekday, std::chrono::year_month_weekday::index, std::chrono::year_month_weekday::weekday_indexed

 

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day (C++20) month (C++20) year (C++20) weekday (C++20) operator/ (C++20) year_month_day (C++20)	year_month_day_last (C++20) year_month_weekday (C++20) year_month_weekday_last (C++20)   weekday_indexed (C++20) weekday_last (C++20) month_day (C++20)	month_day_last (C++20) month_weekday (C++20) month_weekday_last (C++20) year_month (C++20) last_speclast (C++20)(C++20)
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C 风格日期和时间

 

std::chrono::year_month_weekday

成员函数

year_month_weekday::year_month_weekday

year_month_weekday::operator+=year_month_weekday::operator-=

year_month_weekday::yearyear_month_weekday::monthyear_month_weekday::weekdayyear_month_weekday::indexyear_month_weekday::weekday_indexed

year_month_weekday::operator sys_daysyear_month_weekday::operator local_days

year_month_weekday::ok

非成员函数

operator==

operator+operator-

operator<<

辅助类

formatter<std::chrono::year_month_weekday>

hash<std::chrono::year_month_weekday> (C++26)

 

constexpr std::chrono::year year() const noexcept;	(1)	(C++20 起)
constexpr std::chrono::month month() const noexcept;	(2)	(C++20 起)
constexpr std::chrono::weekday weekday() const noexcept;	(3)	(C++20 起)
constexpr unsigned index() const noexcept;	(4)	(C++20 起)
constexpr std::chrono::weekday_indexed weekday_indexed() const noexcept;	(5)	(C++20 起)

返回存储于此 year_month_weekday 对象中的各域的值。

返回值

1) 返回存储的 std::chrono::year 值。

2) 返回存储的 std::chrono::month 值。

3) 返回存储的 std::chrono::weekday 值。

4) 返回存储的星期之日索引。

5) weekday()[index()]。

示例

运行此代码

#include <cassert>
#include <chrono>
 
int main()
{
    constexpr auto ym{std::chrono::year(2021)/std::chrono::January};
    constexpr auto wdi{std::chrono::Wednesday[1]};
    auto ymwdi{ym/wdi};
    const auto index{ymwdi.index() + 1};
    auto weekday{ymwdi.weekday() + std::chrono::days(1)};
    ymwdi = {ymwdi.year()/ymwdi.month()/weekday[index]};
    // 2021 年一月第二个星期四
    assert(std::chrono::year_month_day{ymwdi} == std::chrono::January/14/2021);
}