Temporal.PlainMonthDay.prototype.toString()

The toString() method of {{jsxref("Temporal.PlainMonthDay")}} instances returns a string representing this month-day in the RFC 9557 format.

Syntax#

toString()
toString(options)

Parameters#

• options {{optional_inline}}
• : An object containing the following property:
  • calendarName {{optional_inline}}
  • : Whether to show the calendar annotation ([u-ca=calendar_id]) in the return value. Possible values are:
    • "auto" (default)
    • : Include the calendar annotation if the calendar is not "iso8601". The reference year is included if the calendar is not "iso8601".
    • "always"
    • : Always include the calendar annotation. The reference year is always included too.
    • "never"
    • : Never include the calendar annotation. This makes the returned string not recoverable to the same {{jsxref("Temporal.PlainMonthDay")}} instance, although the month-day value still remains the same. The reference year is included if the calendar is not "iso8601".
    • "critical"
    • : Always include the calendar annotation, and add a critical flag: [!u-ca=calendar_id]. Useful when sending the string to certain systems, but not useful for Temporal itself. The reference year is always included too.

Return value#

A string in the RFC 9557 format representing this month-day. The calendar annotation is included as specified. The reference year is included if a calendar annotation is included or if the calendar is not "iso8601".

Exceptions#

• {{jsxref("RangeError")}}
• : Thrown if any of the options is invalid.
• {{jsxref("TypeError")}}
• : Thrown if options is not an object or undefined.

Examples#

Using toString()#

const md = Temporal.PlainMonthDay.from({ month: 8, day: 1 });
console.log(md.toString()); // '08-01'

const md2 = Temporal.PlainMonthDay.from({
  monthCode: "M08",
  day: 1,
  calendar: "chinese",
});
console.log(md2.toString()); // '1972-09-08[u-ca=chinese]'

Using options#

const isoMD = Temporal.PlainMonthDay.from({ month: 8, day: 1 });
const md = Temporal.PlainMonthDay.from({
  monthCode: "M08",
  day: 1,
  calendar: "chinese",
});
console.log(isoMD.toString({ calendarName: "auto" })); // '08-01'
console.log(md.toString({ calendarName: "auto" })); // '1972-09-08[u-ca=chinese]'
console.log(isoMD.toString({ calendarName: "always" })); // '1972-08-01[u-ca=iso8601]'
console.log(md.toString({ calendarName: "always" })); // '1972-09-08[u-ca=chinese]'
console.log(isoMD.toString({ calendarName: "never" })); // '08-01'
console.log(md.toString({ calendarName: "never" })); // '1972-09-08'
console.log(isoMD.toString({ calendarName: "critical" })); // '1972-08-01[!u-ca=iso8601]'
console.log(md.toString({ calendarName: "critical" })); // '1972-09-08[!u-ca=chinese]'

Specifications#

{{Specifications}}

Browser compatibility#

{{Compat}}

See also#

• {{jsxref("Temporal.PlainMonthDay")}}
• {{jsxref("Temporal/PlainMonthDay/from", "Temporal.PlainMonthDay.from()")}}
• {{jsxref("Temporal/PlainMonthDay/toJSON", "Temporal.PlainMonthDay.prototype.toJSON()")}}
• {{jsxref("Temporal/PlainMonthDay/toLocaleString", "Temporal.PlainMonthDay.prototype.toLocaleString()")}}