How to format date with hours, minutes and seconds when using jQuery UI Datepicker?

Try this fiddle

$(function() {
    $('#datepicker').datepicker({
        dateFormat: 'yy-dd-mm',
        onSelect: function(datetext) {
            var d = new Date(); // for now

            var h = d.getHours();
            h = (h < 10) ? ("0" + h) : h ;

            var m = d.getMinutes();
            m = (m < 10) ? ("0" + m) : m ;

            var s = d.getSeconds();
            s = (s < 10) ? ("0" + s) : s ;

            datetext = datetext + " " + h + ":" + m + ":" + s;

            $('#datepicker').val(datetext);
        }
    });
});