1.html

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
<title>Examples</title>
<meta name="description" content="">
<meta name="keywords" content="">
<link href="" rel="stylesheet">
<script type="text/javascript" src="js/jquery-2.1.4.min.js"></script>
</head>
<body>
	<div class="box">
		123456789
	</div>
    <script type="text/javascript">
    var aa = $(".box")[0];
    alert(aa)
    </script>
</body>
</html>