how to get all data which stored in jquery.data() 
<p>this is the demo code:</p>

<pre><code>  $(document).ready(function(){

    $("button").click(function(e) {
      var value;

      switch ($("button").index(this)) {
        case 0 :
          value = $("div").data("blah");
          break;
        case 1 :
          $("div").data("blah", "hello");
          value = "Stored!";
          break;
        case 2 :
          $("div").data("blah", 86);
          value = "Stored!";
          break;
        case 3 :
          $("div").removeData("blah");
          value = "Removed!";
          break;
      }

      $("span").text("" + value);
    });

  });
  &lt;/script&gt;
  &lt;style&gt;
  div { margin:5px; background:yellow; }
  button { margin:5px; font-size:14px; }
  p { margin:5px; color:blue; }
  span { color:red; }
  &lt;/style&gt;
  &lt;div&gt;A div&lt;/div&gt;
  &lt;button&gt;Get "blah" from the div&lt;/button&gt;
  &lt;button&gt;Set "blah" to "hello"&lt;/button&gt;
  &lt;button&gt;Set "blah" to 86&lt;/button&gt;
  &lt;button&gt;Remove "blah" from the div&lt;/button&gt;
  &lt;p&gt;The "blah" value of this div is &lt;span&gt;?&lt;/span&gt;&lt;/p&gt;
</code></pre>

<p>but , how to get all data(because some key name i don't know ) ??</p>

<p>thanks</p>
