Use jQuery/JS to determine the DAY OF WEEK

Question

Is there a method using either JavaScript or jQuery to determine what day of the week it is? For instance, if the date a user picks in the box is a Sunday, I can alert them.

Answer 1

send date and you will get position of the same day of that month . i.e. 15/02/2018 is Third Thursday.

 /*return day postion and dayname */
    function weekAndDay(date) {
        var arrayWeek =[];
        var date = new Date(date),
        days = ['Sunday','Monday','Tuesday','Wednesday','Thursday','Friday','Saturday'],
        prefixes = ['','First', 'Second', 'Third', 'Fourth', 'Fifth'];
        if (date.getDate() % 7 == 0) {
            var prefixes2 = date.getDate() / 7;
        }else{
            var prefixes2 = Math.ceil(date.getDate() / 7);
        }
        arrayWeek.push({
            'dayPos' : prefixes[prefixes2] ,
            'dayName' : days[date.getDay()]
        });
        return arrayWeek;
    }