<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <style> .active { color: red; } li { cursor: pointer; } </style></head><body> <div id="app"> <div>dfasdfadsf</div> <div>dfasdfadsf</div> <div>dfasdfadsf</div> </div> <ul> </ul> <script src="https://cdn.bootcdn.net/ajax/libs/jquery/3.6.0/jquery.min.js"></script> <script> // 获取app里面的html字符串 var str = $('#app').html(); console.log(str); var str = $('#app').text(); console.log(str); // 给ul添加内容 var str3 = ` <li>第1个li元素</li> <li>第2个li元素</li> <li>第3个li元素</li> <li>第4个li元素</li>`; $('ul').html(str3); </script></body></html>