title: Why the jquery prop() method can not get the the element's value property
body: <p>I have several <code>li</code> element in page:</p>
  
  <pre><code>&lt;li value="a"&gt;a&lt;/li&gt;
  &lt;li value="b"&gt;b&lt;/li&gt;
  &lt;li value="c"&gt;c&lt;/li&gt;
  &lt;li value="d"&gt;d&lt;/li&gt;
  </code></pre>
  
  <p>the I want get the value property when hover on it:</p>
  
  <pre><code>$(function () {
      $('li').live('mouseover', function () {
          console.log($(this).prop('value'));                             
      })
  });
  </code></pre>
  
  <p>but the result is always <code>0</code>,then I try the <code>attr()</code> method, it still can not work ,how can I solve this problem?</p>