效果
代码
<!DOCTYPE html>
<html lang="en"><head><meta charset="UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=edge"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>左侧二级菜单实现</title></head><style>* {margin: 0;padding: 0;}/* 取消所有列表的序号 */ul,li {list-style-type: none;}/* 取消所有超链接的下划线 */a {text-decoration-line: none;color: white;}/* 全部样式 */.all_content {display: flex;}/* 左侧导航栏 */.left_nav {background-color: #222d32;width: 10%;height: 100vh;}/* 外层li */.menu-item {padding: 10px;background-color: #222d32;}.submenu {width: 100%;margin-top: 10px;margin-left: -10px;display: none;background-color: #181f23;}.submenu-li {background-color: #181f23;width: 100%;padding: 10px;}.submenu-link:hover {font-weight: 600;}.menu-item.active .submenu {display: block;}/* 右侧内容 */.right_content {width: 90%;}.content {display: none;/* 隐藏所有内容 */}.content.active {display: block;/* 显示被激活的内容 */}.selected {background-color:#4e73df;/* 设置选中状态的背景色 */}
</style><body><div class="all_content"><div class="left_nav"><ul class="menu"><li class="menu-item"><a href="#" class="menu-link">销售</a><ul class="submenu"><li class="submenu-li"><a href="#"class="submenu-link"data-content-id="content1">功能1</a></li><li class="submenu-li"><a href="#"class="submenu-link"data-content-id="content2">报表1</a></li></ul></li><li class="menu-item"><a href="#" class="menu-link">采购</a><ul class="submenu"><li class="submenu-li"><a href="#"class="submenu-link"data-content-id="content3">功能2</a></li><li class="submenu-li"><a href="#"class="submenu-link"data-content-id="content4">报表2</a></li></ul></li></ul></div><div class="right_content"><div id="content1" class="content">功能1的内容</div><div id="content2" class="content">报表1的内容</div><div id="content3" class="content">功能2的内容</div><div id="content4" class="content">报表2的内容</div></div></div><script>// 获取所有一级菜单项var menuItems = document.querySelectorAll('.menu-item');var contents = document.querySelectorAll('.content');// 为每个一级菜单项添加点击事件处理程序menuItems.forEach(function (menuItem) {var menuLink = menuItem.querySelector('.menu-link');var submenu = menuItem.querySelector('.submenu');menuLink.addEventListener('click', function (e) {e.preventDefault();// 关闭其他一级菜单的展开状态menuItems.forEach(function (item) {if (item !== menuItem) {item.classList.remove('active');}});// 切换当前一级菜单的展开状态menuItem.classList.toggle('active');});});// 为每个二级菜单项添加点击事件处理程序var submenuLinks = document.querySelectorAll('.submenu-link');submenuLinks.forEach(function (link) {link.addEventListener('click', function (e) {e.preventDefault();// 移除所有内容的激活状态contents.forEach(function (content) {content.classList.remove('active');});// 获取被点击项对应的内容IDvar contentId = link.getAttribute('data-content-id');// 添加激活状态到对应的内容var activeContent = document.getElementById(contentId);activeContent.classList.add('active');// 关闭其他一级菜单的展开状态menuItems.forEach(function (menuItem) {menuItem.classList.remove('active');});// 保持对应的一级菜单打开link.closest('.menu-item').classList.add('active');// 移除其他二级菜单的选中状态背景色submenuLinks.forEach(function (submenuLink) {submenuLink.parentElement.classList.remove('selected');});// 给选中的二级菜单添加选中状态背景色link.closest('.submenu-li').classList.add('selected');});});</script></body></html>
