1. <!DOCTYPE html>
    2. <html lang="en">
    4. <head>
    5.     <meta charset="UTF-8">
    6. </head>
    8. <body>
    9.     <div class="box">
    10.         <div>adsfasdf</div>
    11.         <p>sfasdf</p>
    12.         <span>asdfa</span>
    13.         <div>
    14.             <span class="aa">nihao</span>
    15.         </div>
    16.     </div>
    19.     <script src="https://cdn.bootcdn.net/ajax/libs/jquery/3.6.0/jquery.min.js"></script>
    20.     <script>
    21.         var $box = $('.box');
    22.         // span是元素选择器, 也可以换成其他的选择器, 比如id,class
    23.         var $aa = $box.find('.aa')
    24.         console.log($aa);
    25.         // 查找$box所有后代元素
    26.         var $souyou = $box.children()
    27.         console.log($souyou);
    28.     </script>
    29. </body>
    31. </html>