<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>jquery</title>
<script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>
</head>
<body>
<div id="box">
<p class="aa">paa</p>
</div>
<div class="aa"></div>
<div class="aa"></div>
<div class="bb" data-bb="这是自定义标签属性"></div>
<script>
const $boxp = $("p");
const $box = $("#box");
const $boxaa = $("#box .box");
const box = document.getElementById("box");
const $a = $("<a>123</a>");
const a = document.createElement("a");
a.innerHTML = 123;
const $aa = $(".aa");
$aa.each((i,v) =>{
console.log(i);
console.log(v);
})
console.log($aa.length);
const p = $box.get(0);
p.innerHTML = 111;
const $bb = $(".bb");
console.log($bb.data("bb"));
</script>
</body>
</html>
