JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://code.jquery.com/ui/1.11.4/themes/smoothness/jquery-ui.css">
<script src="https://code.jquery.com/ui/1.11.4/jquery-ui.js"></script>
<p>Date:
  <input type="text" id="datepicker">
</p>
<p id="error">

</p>
<button>
  Validate
</button>

JavaScript

$(function() {
  $("#datepicker").datepicker({
    dateFormat: 'yy/mm/dd',
  });

  $('button').click(function() {
    $('#error').text('');
    try {
    var dateParse = $.datepicker.parseDate("yy/mm/dd", $("#datepicker").val());
    } catch (e) {}
    if (dateParse) {
      $('#error').text(dateParse);
    } else {
      $('#error').text('invalid date format');
    }
  });
});