uIsoWeek

Returns the week number defined by ISO 8601

The first week of a year is number 01, which is defined as being the week that contains the first Thursday of the calendar year, which implies that it is also:

The first week that is mostly within the calendar year
The week containing January 4th
The week starting with the Monday nearest to January 1st

The last week of a year, number 52 or 53, therefore is:

The week that contains the last Thursday of the calendar year
The last week that is mostly within the calendar year
The week containing December 28th
The week ending with the Sunday nearest to December 31st

Syntax

number uIsoWeek([modifiers])

Parameters

string modifiers (optional) – List of strings specifying a date or date calculation. Default is the now modifier.

Examples

Example 1 –

uIsoWeek("now") // returns current week number