title: How to send select2 multiple selected option values with form.serialize()?
body: <p>I used select2 to select multiple options in html and want to send selected values as an array with form.serialize() to update database field and I have other input in my form. How can I do this?</p>
  
  <p>html:</p>
  
  <pre><code>&lt;html&gt;
  &lt;select name="number" id="number" required class="js-example basic-multiple" multiple="multiple[]"&gt;
  &lt;option class="select_option" value="1" &gt;1&lt;/option&gt;
  &lt;option class="select_option" value="2" &gt;2&lt;/option&gt;
  &lt;option class="select_option" value="3" &gt;3&lt;/option&gt;
  &lt;/select&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>I want to send  [1,2,3] as part of form.serialize().</p>