Temporal.PlainMonthDay.prototype.calendarId

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The calendarId accessor property of Temporal.PlainMonthDay instances returns a string representing the calendar used to interpret the internal ISO 8601 date.

For a list of commonly supported values, see Intl.Locale.prototype.getCalendars().

The set accessor of calendarId is undefined. You cannot change this property directly. There's no obvious way to create a new Temporal.PlainMonthDay object with a different calendar that represents the same month-day, so you need to convert it to a Temporal.PlainDate object first using toPlainDate(), change the calendar, and then convert it back.

Examples

Using calendarId

js
const md = Temporal.PlainMonthDay.from("07-01");
console.log(md.calendarId); // "iso8601"; default

const md2 = Temporal.PlainMonthDay.from("2021-07-01[u-ca=chinese]");
console.log(md2.calendarId); // "chinese"

Changing calendarId

js
const md = Temporal.PlainMonthDay.from("07-01");
const newMD = md
  .toPlainDate({ year: 2021 })
  .withCalendar("chinese")
  .toPlainMonthDay();
console.log(newMD.monthCode, newMD.day); // "M05" 22

const newMD2 = md
  .toPlainDate({ year: 2022 })
  .withCalendar("chinese")
  .toPlainMonthDay();
console.log(newMD2.monthCode, newMD2.day); // "M06" 3

Specifications

Specification
Temporal proposal
# sec-get-temporal.plainmonthday.prototype.calendarid

Browser compatibility

BCD tables only load in the browser

See also