html
复制代码
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div id="box" class="box"></div>
<div class="box">2</div>
</body>
<script>
const box1 = document.getElementById("box");
console.log("box1：", box1);
const box2 = document.getElementsByTagName("div");
console.log("box2：", box2);
const box3 = document.getElementsByClassName("box");
console.log("box3：", box3);
const box4 = document.querySelector(".box");
console.log("box4：", box4);
const box5 = document.querySelectorAll(".box");
console.log("box5：", box5);
console.log("document.body：", document.body);
console.log("document.documentElement：", document.documentElement);
</script>
</html>
