为什么 html 选项卡在通过 active 设置时不显示其内容?

md *_*ver 5 html javascript css

显示一些选项卡。当 html 页面在浏览器上加载并显示其内容时,它应该显示第一个选项卡信息,因为它被设置为活动状态。但是活动选项卡没有显示其在单击选项卡后正在工作的内容。我只是希望当我在任何选项卡上设置为活动时,它应该显示其内容而无需单击它们。这是我的代码。

<!DOCTYPE html>
<html>
   <head>
      <title></title>
      <style type="text/css">
         .sight_img{
         height: 80%;
         width: 100%;
         }
         .tab {
         overflow: hidden;
         border: 1px solid #ccc;
         background-color: #f1f1f1;
         }
         /* Style the buttons inside the tab */
         .tab button {
         background-color: inherit;
         float: left;
         border: none;
         outline: none;
         cursor: pointer;
         padding: 14px 16px;
         transition: 0.3s;
         font-size: 17px;
         }
         /* Change background color of buttons on hover */
         .tab button:hover {
         background-color: #ddd;
         }
         /* Create an active/current tablink class */
         .tab button.active {
         background-color: #ccc;
         display:block;
         }
         /* Style the tab content */
         .tabcontent {
         display: none;
         padding: 6px 12px;
         -webkit-animation: fadeEffect 1s;
         animation: fadeEffect 1s;
         }
         /* Fade in tabs */
         @-webkit-keyframes fadeEffect {
         from {opacity: 0;}
         to {opacity: 1;}
         }
         @keyframes fadeEffect {
         from {opacity: 0;}
         to {opacity: 1;}
         }
      </style>
   </head>
   <body>
      <div class="tab">
         <button class="tablinks btn active" onclick="openCity(event, 'Description')">Description</button>
         <button class="tablinks" onclick="openCity(event, 'Avalability')">Avalability</button>
         <button class="tablinks" onclick="openCity(event, 'Itinerary')">Itinerary</button>
         <button class="tablinks" onclick="openCity(event, 'Policy')">Policy</button>
      </div>
      <!-- // content-tabs-i // -->
      <div id="Description" class="tabcontent">
         <h3>Description</h3>
      </div>
      <div id="Avalability" class="tabcontent">
         <h3>Avalability</h3>
      </div>
      <div id="Itinerary" class="tabcontent">
         <h3>Itinerary</h3>
      </div>
      <div id="Policy" class="tabcontent">
         <h3>Policy</h3>
      </div>
   </body>
</html>
<script>
   function openCity(evt, cityName) {
     var i, tabcontent, tablinks;
     tabcontent = document.getElementsByClassName("tabcontent");
     for (i = 0; i < tabcontent.length; i++) {
       tabcontent[i].style.display = "none";
     }
     tablinks = document.getElementsByClassName("tablinks");
     for (i = 0; i < tablinks.length; i++) {
       tablinks[i].className = tablinks[i].className.replace(" active", "");
     }
     document.getElementById(cityName).style.display = "block";
     evt.currentTarget.className += " active";
   }
</script>
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在这里你可以看到。单击选项卡后,即使我在第一个选项卡上使用了活动类,它也会显示其选项卡的内容。我只是希望那些选项卡应该显示其由活动设置的内容,而无需单击它。

小智 2

添加style="display: block;"到您的 tabcontent div 以显示您的默认 div。

<!DOCTYPE html>
<html>
   <head>
      <title></title>
      <style type="text/css">
         .sight_img{
         height: 80%;
         width: 100%;
         }
         .tab {
         overflow: hidden;
         border: 1px solid #ccc;
         background-color: #f1f1f1;
         }
         /* Style the buttons inside the tab */
         .tab button {
         background-color: inherit;
         float: left;
         border: none;
         outline: none;
         cursor: pointer;
         padding: 14px 16px;
         transition: 0.3s;
         font-size: 17px;
         }
         /* Change background color of buttons on hover */
         .tab button:hover {
         background-color: #ddd;
         }
         /* Create an active/current tablink class */
         .tab button.active {
         background-color: #ccc;
         display:block;
         }
         /* Style the tab content */
         .tabcontent {
         display: none;
         padding: 6px 12px;
         -webkit-animation: fadeEffect 1s;
         animation: fadeEffect 1s;
         }
         /* Fade in tabs */
         @-webkit-keyframes fadeEffect {
         from {opacity: 0;}
         to {opacity: 1;}
         }
         @keyframes fadeEffect {
         from {opacity: 0;}
         to {opacity: 1;}
         }
      </style>
   </head>
   <body>
      <div class="tab">
         <button class="tablinks btn active" onclick="openCity(event, 'Description')">Description</button>
         <button class="tablinks" onclick="openCity(event, 'Avalability')">Avalability</button>
         <button class="tablinks" onclick="openCity(event, 'Itinerary')">Itinerary</button>
         <button class="tablinks" onclick="openCity(event, 'Policy')">Policy</button>
      </div>
      <!-- // content-tabs-i // -->
      <div id="Description" class="tabcontent" style="display: block;">
         <h3>Description</h3>
      </div>
      <div id="Avalability" class="tabcontent">
         <h3>Avalability</h3>
      </div>
      <div id="Itinerary" class="tabcontent">
         <h3>Itinerary</h3>
      </div>
      <div id="Policy" class="tabcontent">
         <h3>Policy</h3>
      </div>
   </body>
</html>
<script>
   function openCity(evt, cityName) {
     var i, tabcontent, tablinks;
     tabcontent = document.getElementsByClassName("tabcontent");
     for (i = 0; i < tabcontent.length; i++) {
       tabcontent[i].style.display = "none";
     }
     tablinks = document.getElementsByClassName("tablinks");
     for (i = 0; i < tablinks.length; i++) {
       tablinks[i].className = tablinks[i].className.replace(" active", "");
     }
     document.getElementById(cityName).style.display = "block";
     evt.currentTarget.className += " active";
   }
</script>
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