The withCalendar() method of Temporal.PlainDateTime instances returns a new Temporal.PlainDateTime object representing this date-time interpreted in the new calendar system. Because all Temporal objects are designed to be immutable, this method essentially functions as the setter for the date-time's calendarId property.
To replace the date-time component properties, use the with() method instead.
withCalendar(calendar)calendarA string that corresponds to the calendarId property. See Intl.supportedValuesOf() for a list of commonly supported calendar types.
A new Temporal.PlainDateTime object, representing the date-time specified by the original PlainDateTime, interpreted in the new calendar system.
TypeErrorThrown if calendar is not a string.
RangeErrorThrown if calendar is not a valid calendar identifier.
const dt = Temporal.PlainDateTime.from("2021-07-01T12:34:56");
const newDT = dt.withCalendar("islamic-umalqura");
console.log(newDT.toLocaleString("en-US", { calendar: "islamic-umalqura" }));
// 11/21/1442 AH, 12:34:56 PM