localStorage : store checkboxes automatically checked

I have something like this in php:

    if(isset($_POST['submit']){ 
            $check = in_array($row['service_object_id'], $values) ? 'checked' : ''; 
    }                       
    echo '<input type="checkbox" class="faChkRnd" id="'.$row['service_object_id'].'" name="list[]" value="'.$row['service_object_id'].'" '.$check.'>';

Each time I press a submit button, it will check the checkboxes with values inside $check. It's working good but I want to store the checkboxes checked in localStorage automatically after pressing the button.

I already use this script to store them after click, but it won't work automatically :

    <script type = "text/javascript"> 
$('.faChkRnd').on('click', function() {
  var fav, favs = [];
  $('.faChkRnd').each(function() { // run through each of the checkboxes
    fav = {id: $(this).attr('id'), value: $(this).prop('checked')};
    favs.push(fav);
  });
  localStorage.setItem("favorites", JSON.stringify(favs));
});

$(document).ready(function() {
  var favorites = JSON.parse(localStorage.getItem('favorites'));
  if (!favorites.length) {return};
  console.debug(favorites);

  for (var i=0; i<favorites.length; i++) {
    console.debug(favorites[i].value == 'on');
    $('#' + favorites[i].id ).prop('checked', favorites[i].value);
  }
});
</script>

Any ideas ? Thank you !