The weekOfYear accessor property of Temporal.PlainDateTime instances returns a positive integer representing the 1-based week index in the yearOfWeek of this date, or undefined if the calendar does not have a well-defined week system. The first week of the year is 1. It is calendar-dependent.

The set accessor of weekOfYear is undefined. You cannot change this property directly. To create a new Temporal.PlainDateTime object with the desired new weekOfYear value, use the add() or subtract() method with the appropriate number of weeks.

For general information and more examples, see Temporal.PlainDate.prototype.weekOfYear.

Examples

Using weekOfYear

const dt = Temporal.PlainDateTime.from("2021-07-01");
console.log(dt.weekOfYear); // 26

Specifications

Browser compatibility

See also

• Temporal.PlainDateTime
• Temporal.PlainDateTime.prototype.with()
• Temporal.PlainDateTime.prototype.add()
• Temporal.PlainDateTime.prototype.subtract()
• Temporal.PlainDateTime.prototype.yearOfWeek
• Temporal.PlainDateTime.prototype.dayOfWeek
• Temporal.PlainDateTime.prototype.daysInWeek
• Temporal.PlainDateTime.prototype.daysInYear
• Temporal.PlainDate.prototype.weekOfYear