Get end date form start date and number of days

Question

I would like to set the value of end date from numbers of days and start day selected in the form. I have tried this but it doesn't work.

$(document).on('change', "#startDate", function (e) {
    e.preventDefault();
    var nbDays = $("#nbDays").val();
    var startDt = $("#startDate").val();
    var endDt = $("#endDate").val();

    $("#endDate").val(startDt + nbDays)   ;

});

this may help a bit: http://stackoverflow.com/questions/542938/how-do-i-get-the-number-of-days-between-two-dates-in-javascript — Darcey Mckelvey, May 01 '16 at 19:34

bjelli · Accepted Answer · 2016-05-01T19:54:07.640

jQuery is no big help handling dates. try moment.js to do the date manipulation!

moment.js can parse a string into a date object:

startDate = moment(startDate_string);

it can do addition:

endDate = startDate.add( nbdays, 'days');

and it can help with formatting the date as a string again (you might change this according to the date conventions of your language/locale)

endDate.format('MM/DD/YYYY');

See https://jsfiddle.net/bjelline/24440qqr/ for full example code.

score 0 · Answer 2 · edited May 23 '17 at 10:33

Use the javascript Date object. This questions has been answered multiple places. Here's one example from a previous SO thread modified to your specs:

$(document).on('change', "#startDate", function (e) {
    e.preventDefault();
    var nbDays = $("#nbDays").val();
    var startDt = $("#startDate").val();

    //Depeneding on the what the startDt value is, 
    //you may have to use a different date constructor
    var dat = new Date(startDt);
    dat.setDate(dat.getDate() + nbDays)

    //Depending on what the required output format is,
    //you may want to grab the MM DD YY of date and format
    //to your specs
    $("#endDate").val(dat);

});

Here's the documentation on the javascript Date object.

Get end date form start date and number of days

2 Answers2