<!DOCTYPE html>
<head>
<meta charset="UTF-8">
<title>jQuery选择器</title>
<script type="text/javascript" src="js/jquery-3.3.1.js"></script>
<script type="text/javascript">
$(function(){
$("*")
$("#one")
$(".two")
$("div")
});
</script>
</head>
<body>
<div id="one">Category: Selectors</div>
<div class="two">Category: Selectors</div>
<div class="two">Category: Selectors</div>
</body>
</html>
选择器有哪些
全部、类、标签、ID、多个
选择器返回的是一个jQuery对象
http://api.jquery.com/category/selectors/basic-css-selectors/