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HTML

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CSS

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <h2>标签（选项卡）</h2>
<p>单击选项卡菜单内的按钮:</p>
<!-- 选项卡链接 -->
<div class="tab">
  <button class="tablinks" onclick="openCity(event, 'London')">London</button>
  <button class="tablinks" onclick="openCity(event, 'Paris')">Paris</button>
  <button class="tablinks" onclick="openCity(event, 'Tokyo')">Tokyo</button>
</div>

<!-- 选项卡内容 -->
<div id="London" class="tabcontent" style="display:block;">
  <h3>London</h3>
  <p>London is the capital city of England.</p>
</div>

<div id="Paris" class="tabcontent">
  <h3>Paris</h3>
  <p>Paris is the capital of France.</p>
</div>

<div id="Tokyo" class="tabcontent">
  <h3>Tokyo</h3>
  <p>Tokyo is the capital of Japan.</p>
</div>
!

CSS 

              
                /* 设置选项卡的样式 */
.tab {
  overflow: hidden;
  border: 1px solid #ccc;
  background-color: #f1f1f1;
}

/* 设置用于打开选项卡内容的按钮的样式 */
.tab button {
  background-color: inherit;
  float: left;
  border: none;
  outline: none;
  cursor: pointer;
  padding: 14px 16px;
  transition: 0.3s;
}

/* 更改悬停按钮的背景色 */
.tab button:hover {
  background-color: #ddd;
}

/* 创建活动/当前tablink类 */
.tab button.active {
  background-color: #ccc;
}

/* 设置选项卡内容的样式 */
.tabcontent {
  display: none;
  padding: 6px 12px;
  border: 1px solid #ccc;
  border-top: none;
  /*如果要淡入标签内容，请添加以下 CSS*/
  animation: fadeEffect 1s; /* 褪色效果需要1秒 */
}
/* 从零变为完全不透明度 */
@keyframes fadeEffect {
  from {opacity: 0;}
  to {opacity: 1;}
}
!

JS 

              
                function openCity(evt, cityName) {
  // 声明所有变量
  var i, tabcontent, tablinks;

  // 使用class=“tabcontent”获取所有元素并隐藏它们
  tabcontent = document.getElementsByClassName("tabcontent");
  for (i = 0; i < tabcontent.length; i++) {
    tabcontent[i].style.display = "none";
  }

  // 使用class=“tablinks”获取所有元素并删除类“active”
  tablinks = document.getElementsByClassName("tablinks");
  for (i = 0; i < tablinks.length; i++) {
    tablinks[i].className = tablinks[i].className.replace(" active", "");
  }

  // 显示当前选项卡，并向打开该选项卡的按钮添加“活动”类
  document.getElementById(cityName).style.display = "block";
  evt.currentTarget.className += " active";
}
!
999px

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