<html>
<head>
<style>
h1:before
{
counter-increment:section;
content:"第 " counter(section) " 部分：";
}
</style>
</head>
<body>
<p>点击“尝试一下”按钮设置 BODY 元素的 counter-reset 属性：</p>
<button onclick="myFunction()">尝试一下</button>
<h1>HTML 教程</h1>
<h1>JavaScript 教程</h1>
<h1>CSS 教程</h1>
<script>
function myFunction()
{
document.body.style.counterReset="section";
}
</script>
</body>
</html>