JS 获取 HTML DOM 元素的方法

<!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>