Clear Multiselect Lookup

Question

I am trying to add a button for my users to clear a multiselect lookup value using JQuery or Javascript.

I have found some information about setting a default value on a single select lookup, but not the opposite.

I believe I can get the field using get_item("field name"). Is there a built in method for removing selected items?

Thanks, Patrick

Answer 1

Clear it? Would it be good enough to just move the items back to where they came from, by selecting them on the right side and clicking the button.

Something like this:

$('.ms-formbody').filter(function() {
  return $(this).html().match(/spfieldlookup/i) && $(this).find('select').size() >= 1;
}).each(function() {
  var $btn = $('<button>').text('Clear');
  var $select = $(this).find('select:last');
  var $remove = $(this).find('button:last');
  $btn.click(function() {
    $select.val($select.find('option').map(function() {
      return $(this).val();
    }).toArray());
    $remove.removeAttr('disabled').click();
    return false;
  });
  $(this).prepend($btn);
});​