<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<div id="main">
<span>AAA</span>
</div>
</body>
</html>
<script>
var obj = document.getElementById("main");
console.log(obj);
</script>
document.getElementById获取的数据:
这就是obj,对于后面的学习非常重要
