yige.org 试一个

<html>
<head>
  <style>p { color:red; }</style>
  <script type="text/javascript" src="jquery.js"></script>
</head>

<body>
<form method="post" action="">
  <fieldset>
    <div>
      <label for="two">2</label>
      <input type="checkbox" value="2" id="two" name="number[]">
    </div>
    <div>
      <label for="four">4</label>
      <input type="checkbox" value="4" id="four" name="number[]">
    </div>
    <div>
      <label for="six">6</label>
      <input type="checkbox" value="6" id="six" name="number[]">
    </div>
    <div>
      <label for="eight">8</label>
      <input type="checkbox" value="8" id="eight" name="number[]">
    </div>
  </fieldset>
</form>

<p><b>Values: </b></p>

<script>
  $("p").append($(':checkbox').map(function() {
    return this.id;
  }).get().join(','));
</script>

</body>
</html>
结果:
编辑上面的代码，点击查看结果。
yige.org - 试一个