根据给定的类名匹配元素

node2:/var/www/html/jquery/aa#cat a11.html 
<div class="test01">oracle维护</div>
<script type="text/javascript" src="jquery-2.2.2.min.js"></script>
<script type="text/javascript" src="a11.js"></script>


node2:/var/www/html/jquery/aa#cat a11.js
var str1=$(".test01").html();
console.log(str1);