jQuery ui.datepicker on 'select' element

Question

I have a select element with a couple of dates but I also want to give the possibility of picking a date from the datepicker so I have the following code that displays a calendar icon next to the select field.

<select name="birthday" >
     <option value="${merge0.birthday}">${merge0.birthday}</option>
     <option value="${merge1.birthday}">${merge1.birthday}</option>                        
</select>
<input type="hidden" id="bday_icon" />

Then, this is my datepicker script

$("#bday_icon").datepicker(
            {
                changeMonth: true,
                changeYear: true,
                showOn: 'button',
                buttonImage: 'cal/images/calendar.gif',
                buttonImageOnly: true,
                onSelect: function(dateText, inst) {
                    var field = document.getElementsByNameByName("birthday");
                    var opt = document.createElement('option');
                    opt.text = dateText;
                    opt.value = dateText;
                    field.add(opt, null);
            }
            });

Shouldn't the function onSelect, add a new option to the select html element? can't you see what it's wrong?

Thanks.

Update 1:

onSelect: function(dateText, inst) {
      var opt = $('<option />').attr('value', dateText).text(dateText);
      $('select[name=birthday]').append(opt);
      }

Works perfect, only remark that I needed to mark as selected the new option so just edit like: $('<option selected/>')

Answer 1

Unless they're some of your functions, I'm not really sure what .add() and getElementsByNameByName() are. I can't seem to find add in the jQuery api.

Also, when working with jQuery widgets, I prefer to use jQuery selectors:

onSelect: function(dateText, inst) {
    var opt = $('<option />').attr('value', dateText).text(dateText);
    $('select[name=birthday]').append(opt);
}

Works for me.