jquery - Remove Select2's last selection? -

i want create little function blocks user selecting more 3 items multi select list. found useful things on web, allowed me launch alert when user selects more 3 items. however, can't find way remove last selected item.

so far, here's jquery:

$('.metiersmission').change(function(event) { if ($(this).val().length > 3) {     alert('vous ne pouvez choisir que 3 métiers');     $(this).select2('val', ''); } }}); 

with code, if user selects more 3 items, code deletes everything user ever selected, not want. can't find anywhere, has idea?

thank in advance

you can listen change event , count selected options. if selected options 3, disable other options:

$(document).on('change', 'select', function() {    var = $(this);    var val = that.val();    if (val.length > 2) {      // find every unselected option , disable them      that.find('option').not(':selected').attr('disabled','disabled');    } else {      // enable options      that.find('option').removeattr('disabled');    }  });

select { width:250px; height:150px }

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.0.0/jquery.min.js"></script>  <select multiple>    <option value="volvo">volvo</option>    <option value="saab">saab</option>    <option value="opel">opel</option>    <option value="audi">audi</option>    <option value="citroen">citroen</option>    <option value="peugeot">peugeot</option>  </select>