title: Checkbox doesn't work with Ajax jQuery
body: <p>I have multiple inputs in my form but only <code>input="text"</code> works: the checkbox and radio are not working (hidden input doesn't work either)</p>
  
  <p>I'm using</p>
  
  <pre><code>&lt;form id="form"&gt;
   &lt;div&gt;
   &lt;input type="text" name="val_1"&gt;
   &lt;input type="text" name="val_2"&gt;
   &lt;/div&gt;
  
   &lt;div&gt;
   &lt;input type="checkbox" name="val_3" value="1"&gt; 
   &lt;input type="radio" name="val_4" value="1"&gt;
   &lt;/div&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>and in JS:</p>
  
  <pre><code>type: "POST", 
  url: 'page.php', 
  data: $("#form").serialize(),
  async: false,
  </code></pre>
  
  <p>With <code>echo print_r($_POST)</code>, I have just </p>
  
  <pre><code>Array
  (
      [val_1] =&gt; test
      [val_2] =&gt; test
  )
  </code></pre>
  
  <p>Why are <code>val_3</code> and <code>val_4</code> not working?</p>