bootstrap flex 不将内容居中答案

【问题标题】：bootstrap flex do not center the contentbootstrap flex 不将内容居中
【发布时间】：2019-12-22 09:39:55
【问题描述】：

bootstrap flex 不将内容居中

<div class="d-flex flex-row bd-highlight mb-3">
  <div class="p-2 bd-highlight text-left"><i class="fa fa-chevron-left" aria-hidden="true"></i></div>
  <div class="p-2 bd-highlight text-muted text-center justify-content-center" style="text-transform: uppercase;">comments</div>
  <div class="p-2 bd-highlight">Flex item 3</div>
</div>

我正在使用 bootstrap 4，不知何故 class text-center justify-content-center 不起作用，有人可以帮忙吗？

【问题讨论】：

标签： html css twitter-bootstrap bootstrap-4 flexbox

【解决方案1】：

Bootstrap 4 justify classes 需要应用于行（使用d-flex 类），而不是列。

将 justify-content-center 转移到父级，使您的元素按预期居中。

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl" crossorigin="anonymous"></script>

<div class="d-flex flex-row bd-highlight mb-3 justify-content-center">
  <div class="p-2 bd-highlight text-left"><i class="fa fa-chevron-left" aria-hidden="true"></i></div>
  <div class="p-2 bd-highlight text-muted" style="text-transform: uppercase;">comments</div>
  <div class="p-2 bd-highlight">Flex item 3</div>
</div>

请注意，这会将所有元素居中。如果您正在寻找“左-中-右”布局（以便只有中间元素居中），那么您需要justify-content-between：

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl" crossorigin="anonymous"></script>

<div class="d-flex flex-row bd-highlight mb-3 justify-content-between">
  <div class="p-2 bd-highlight text-left"><i class="fa fa-chevron-left" aria-hidden="true"></i></div>
  <div class="p-2 bd-highlight text-muted" style="text-transform: uppercase;">comments</div>
  <div class="p-2 bd-highlight">Flex item 3</div>
</div>

【讨论】：

还有justify-content-around——这真的取决于你想要的外观，但很可能确实是justify-content-between :)