在Bootstrap.css文件中找不到“visible-xs-block”源代码

Question

我正在学习Bootstrap。 在我的项目中，＆＃34; visible-xs-block＆＃34;是一个班级名称。但我在Bootstrap.css文件中找不到“visible-xs-block”源代码

＆＃13;

＆＃13;

<div class="row">
  <div class="col-xs-6 col-sm-4">.col-xs-6 .col-sm-4</div>
  <div class="col-xs-6 col-sm-4">.col-xs-6 .col-sm-4</div>
  <!-- Optional: clear the XS cols if their content doesn't match in height -->
  <div class="clearfix visible-xs-block"></div>
  <div class="col-xs-6 col-sm-4">.col-xs-6 .col-sm-4</div>
</div>

＆＃13;

＆＃13;

＆＃13;

在哪里找到源代码？

Answer 1

这是：

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="top">
  <div class="header">
    <h4 class="title">Title 1</h4>
  </div>
  <div class="body">
    <div id="someDiv">
      <div class="someOtherDiv">
        <div class="OneMoreDiv">
          <button id="SomeButton" class="SomeButtonClass">button</button>
        </div>
      </div>
    </div>
  </div>
</div>
<div class="top">
  <div class="header">
    <h4 class="title">Title 2</h4>
  </div>
  <div class="body">
    <div id="someDiv">
      <div class="someOtherDiv">
        <div class="OneMoreDiv">
        </div>
      </div>
    </div>
  </div>
</div>

Answer 2

.visible-xs-block是来自bootstrap 3的旧类。它在bootstrap 4中不再存在。请参阅migration hints。