Get week of the month

Question

How can i get the week number of month using javascript / jquery?

For ex.:

First Week: 5th July, 2010. / Week Number = First monday

Answer 1

This is a few years on, but I've needed to use this functionality recently and, for certain dates in years 2016/2020 (such as January 31st), none of the code here works.

It's not the most efficient by any means, but hopefully this helps someone out as it's the only thing I could get working for those years along with every other year.

Date.prototype.getWeekOfMonth = function () {
    var dayOfMonth = this.getDay();
    var month = this.getMonth();
    var year = this.getFullYear();
    var checkDate = new Date(year, month, this.getDate());
    var checkDateTime = checkDate.getTime();
    var currentWeek = 0;

    for (var i = 1; i < 32; i++) {
        var loopDate = new Date(year, month, i);

        if (loopDate.getDay() == dayOfMonth) {
            currentWeek++;
        }

        if (loopDate.getTime() == checkDateTime) {
            return currentWeek;
        }
    }
};