我以前从未遇到过,而且我很难找到解决方案。当在引导程序中具有等于medium的列时,如下所示:
<h1 class="text-center">Hello, world!</h1>
  <div class="container">
      <div class="row">
          <div class="col-md-12 text-center">
              <h1>vicki williams</h1>
          </div>
      </div>
  </div>
但是当使列等于超小时,如下所示:
 <div class="container">
      <div class="row">
          <div class="col-xs-12 text-center">
              <h1>vicki williams</h1>
          </div>
      </div>
  </div>
是否有一些我不理解的引导概念,或者这实际上是我认为是错误的。我从来没有遇到过这个问题,因为我的文字在过去一直与xs对齐。任何帮助将不胜感激。这是我完整的代码:
<!DOCTYPE html>
<html lang="en">
  <head>
    <!-- Required meta tags -->
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
    <!-- Bootstrap CSS -->
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/css/bootstrap.min.css" integrity="sha384-rwoIResjU2yc3z8GV/NPeZWAv56rSmLldC3R/AZzGRnGxQQKnKkoFVhFQhNUwEyJ" crossorigin="anonymous">
  </head>
  <body>
    <h1 class="text-center">Hello, world!</h1>
      <div class="container">
          <div class="row">
              <div class="col-xs-12 text-center">
                  <h1>vicki williams</h1>
              </div>
          </div>
      </div>
    <!-- jQuery first, then Tether, then Bootstrap JS. -->
    <script src="https://code.jquery.com/jquery-3.1.1.slim.min.js" integrity="sha384-A7FZj7v+d/sdmMqp/nOQwliLvUsJfDHW+k9Omg/a/EheAdgtzNs3hpfag6Ed950n" crossorigin="anonymous"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/tether/1.4.0/js/tether.min.js" integrity="sha384-DztdAPBWPRXSA/3eYEEUWrWCy7G5KFbe8fFjk5JAIxUYHKkDx6Qin1DkWx51bBrb" crossorigin="anonymous"></script>
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/js/bootstrap.min.js" integrity="sha384-vBWWzlZJ8ea9aCX4pEW3rVHjgjt7zpkNpZk+02D9phzyeVkE+jo0ieGizqPLForn" crossorigin="anonymous"></script>
  </body>
</html>
          

col-xs-*在最新的v4版本中不再存在,这就是您看到此内容的原因。在col-xs-12不具有设定宽度的喜欢你的100%col-md-12。检查DevTools以查看所有内容,并查看此Pull