Question

How to get jQuery UI Datepicker selected date to a PHP Session variable when a date selected by user?

Answer 1

Make an AJAX call when the onSelect is trigged.. Just dummy code you can play with:

        $('.selector').datepicker({
                 onSelect: function(dateText, inst) { 
                       $.ajax({
                             url: "myPHPscript.php?selecteddate=" + dateText,
                               success: function(){
                                 $(this).addClass("done");
                            }
                        });
                     }
        });