如何根据给定的no.of.days更改日期值

i have one datepicker in my form it get some default date from database.now i need to add one textbox asking no.of.days based on textbox value the previous datepicker value get changed.

Eg : in that datepicker column the date is 03-09-15.i give no.of.days as 10 it get chnaged to 13-09-15 how i achieve this

When changing the date from the code, you'd use a setDate method:

HTML :

<div id="date"></div>

JavaScript :

$(function() {
    $("#date").datepicker();

    //handle date here. It is passed as var. So u can make changes here

   var date = '01/09/2014';

   $("#date").datepicker('setDate', date);
}); 

FIDDLE