title: How to handle multi-select boxes in a zend framework form?
body: <p>Just wondering how it works and how to handle the information.</p>
  
  <p>Let's say I have a form like this:</p>
  
  <pre><code>$multi = new Zend_Form_Element_Multiselect('users');
  $multi-&gt;setMultiOptions(array(
      //'option value' =&gt; 'option label'
      '21' =&gt; 'John Doe',
      '22' =&gt; 'Joe Schmoe',
      '23' =&gt; 'Foobar Bazbat'
  ));
  $form-&gt;addElement($multi);
  </code></pre>
  
  <p>If a user selects one, or multiple values from a multi-select box...</p>
  
  <ul>
  <li>How do I get the value that the user selected?</li>
  <li>Does it return in array? or what?</li>
  <li>How can I tell how many items the user selected?</li>
  </ul>