JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://multidatespickr.sourceforge.net/jquery-ui.multidatespicker.js"></script>
<input id="datePick" type="text"/>
<button class="get_dates">Get Dates</button>

JavaScript

$('#datePick').multiDatesPicker({ dateFormat: 'yy-mm-dd' });
$('.get_dates').click(function() {
 	alert($('#datePick').multiDatesPicker('getDates').length);
});