Get week of year in JavaScript like in PHP

Question

How do I get the current weeknumber of the year, like PHP\'s date(\'W\')?

It should be the ISO-8601 week number of year, weeks starting

Answer 1

Jacob Wright's Date.format() library implements date formatting in the style of PHP's date() function and supports the ISO-8601 week number:

new Date().format('W');

It may be a bit overkill for just a week number, but it does support PHP style formatting and is quite handy if you'll be doing a lot of this.