How to get week's first day with week number and year using javascript

Question

We need to implement a functionality in javascript that provides particular week's first day given the week number and year as inputs. This should be a javascript function which expects week number and year as inputs and outputs first day (as date).

Ex: Get week 3 of 2016 year should return Jan 11, 2016.

I have checked ways of getting week's first day using month approach. But, don't know how to get week's first day based on week number.

Please help me in this regard.

Hope this helps http://stackoverflow.com/questions/16590500/javascript-calculate-date-from-week-number — Narendra CM, Jan 13 '16 at 09:11

score 1 · Answer 1 · edited May 23 '17 at 11:44

Try this solution

function getDateOfISOWeek(w, y) {
    var simple = new Date(y, 0, 1 + (w - 1) * 7);
    var dow = simple.getDay();
    var ISOweekStart = simple;
    if (dow <= 5)
        ISOweekStart.setDate(simple.getDate() - simple.getDay() + 1);
    else
        ISOweekStart.setDate(simple.getDate() + 8 - simple.getDay());
    return ISOweekStart;
}

Little modified version from javascript calculate date from week number

How to get week's first day with week number and year using javascript

1 Answers1