abstract：<!DOCTYPE html><html><head><meta charset="UTF-8"><title>Document</title><script type="text/javascript" src="js/jquery-3.3.1.min.js"
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Document</title>
<script type="text/javascript" src="js/jquery-3.3.1.min.js"></script>
<style type="text/css">
.box{
width: 200px;
background: red;
}
</style>
<script type="text/javascript">
$(document).ready(function(){
$('div').toggleClass('box');
$('p').attr('.box');
$('button').click(function(){
$('p').removeAttr('box');
$('p').html('内容被修改了');
$('span').html('<h1>span被替换</h1>');
})
})
</script>
</head>
<body>
<div>我是DIV</div>
<p>P元素</p>
<span>行内元素</span>
<button>点击</button>
</div>
</body>
</html>
