Profile: laetitiat

Problem: I would like to access the selected date value in a datepicker field using the onClose event.

Solution: You can access the selected day, month, and year in the second parameter of the callback function. Here's an example:

jQuery(document).ready(function(){
  jQuery('input[name="wpcf-start-date[display-only]"]').datepicker("option", "onClose", function(dateText,inst){
    console.log(inst.selectedDay + ' ' + inst.selectedMonth + ' ' + inst.selectedYear);
  });
});

Keep in mind that in JavaScript month is a zero-based index, so August will be 7.

Relevant Documentation:
http://api.jqueryui.com/datepicker/#option-onClose
https://www.w3schools.com/js/js_date_methods.asp