思路：首先获取所有的Tab按钮和Tab内容区域，然后为每个Tab按钮添加点击事件监听器。当用户点击一个Tab按钮时，它会将该按钮设置为active，并将对应的Tab内容区域设置为active。其他的Tab按钮和内容区域则被设置为非active状态。这个例子展示了如何使用面向对象的方法来处理DOM元素的类的添加和移除，从而实现Tab切换的功能。
1. index.html：
<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>Document</title><style>.tabLi {display: flex;}.tab {width: 60px;height: 30px;line-height: 30px;text-align: center;margin-left: 10px;border: 1px solid blue;}.tab-active {color: red;} .tab-content {display: none;margin-top: 30px;}.tab-content-active {color: red;display: block;}</style>
</head>
<body><div id="tabs"><div class="tabLi"><div class="tab tab-active" data-for="tab1">Tab 1</div><div class="tab" data-for="tab2">Tab 2</div><div class="tab" data-for="tab3">Tab 3</div></div><div class="tab-content tab-content-active" id="tab1">Content for tab 1</div><div class="tab-content" id="tab2">Content for tab 2</div><div class="tab-content" id="tab3">Content for tab 3</div></div><script src="./index.js"></script>
</body>
</html>
2.index.js:
document.addEventListener('DOMContentLoaded', function() {var tabs = document.querySelectorAll('.tab');var tabContents = document.querySelectorAll('.tab-content');tabs.forEach(function(tab) {tab.addEventListener('click', function() {var activeTab = document.querySelector('.tab-active');if (activeTab) {activeTab.classList.remove('tab-active');}this.classList.add('tab-active');var activeContent = document.querySelector('.tab-content-active');if (activeContent) {activeContent.classList.remove('tab-content-active');}var selectedTab = this.getAttribute('data-for');document.getElementById(selectedTab).classList.add('tab-content-active');});});
});
