Question

在上面的代码中，我试图仅使用h1在没有任何CSS样式的情况下将bootstrap 4元素在图像上垂直和水平居中。 该怎么做？

<link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" rel="stylesheet"/>

<div id="navbar" class="p-2">
        <nav class="navbar navbar-expand-lg navbar-light">
            <a class="navbar-brand" href="BR Architects"><span id="BR">BR</span> Architects</a>
            <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNavDropdown" aria-controls="navbarNavDropdown" aria-expanded="false" aria-label="Toggle navigation">
                <span class="navbar-toggler-icon"></span>
            </button>
            <div class="collapse navbar-collapse" id="navbarNavDropdown">
                <ul class="navbar-nav ml-auto">
                    <li class="nav-item">
                        <a class="nav-link" href="#">Projects</a>
                    </li>
                    <li class="nav-item">
                        <a class="nav-link" href="#">About</a>
                    </li>
                    <li class="nav-item">
                        <a class="nav-link" href="#">Contact</a>
                    </li>
                </ul>
            </div>
        </nav>         
    </div>

    <div id="header-img">
        <div class="card text-center">
            <img class="card-img" src="https://www.w3schools.com/w3images/architect.jpg" alt="Card image">
            <div class="card-img-overlay">
              <h1 class="card-title"><span class="text-white">BR</span> Architects</h1>   
            </div>
          </div>
    </div>

谢谢！

Answer 1

目前我能想到的最简单的解决方案

将此行添加到您的card-img-overlay“ d-flex justify-content-center align-items-center”

示例：

<div class="card-img-overlay d-flex justify-content-center align-items-center">
       <h1 class="card-title "><span class="text-white">BR</span> Architects</h1>   
 </div>

希望这会有所帮助。

Answer 2

一种解决方案是将d-flex类添加到card-img-overlay中，然后将justify-content-center类用于水平对齐，将align-items-center类用于垂直对齐。

<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.6/umd/popper.min.js" integrity="sha384-wHAiFfRlMFy6i5SRaxvfOCifBUQy1xHdJ/yoi7FRNXMRBu5WHdZYu1hA6ZOblgut" crossorigin="anonymous"></script>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.2.1/css/bootstrap.min.css" integrity="sha384-GJzZqFGwb1QTTN6wy59ffF1BuGJpLSa9DkKMp0DgiMDm4iYMj70gZWKYbI706tWS" crossorigin="anonymous">
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.2.1/js/bootstrap.min.js" integrity="sha384-B0UglyR+jN6CkvvICOB2joaf5I4l3gm9GU6Hc1og6Ls7i6U/mkkaduKaBhlAXv9k" crossorigin="anonymous"></script>


<div id="header-img">
  <div class="card">
    <img class="card-img" src="https://www.w3schools.com/w3images/architect.jpg" alt="Card image">
    <div class="card-img-overlay d-flex align-items-center justify-content-center">
      <h1 class="card-title">
        <span class="text-white">BR</span> Architects
      </h1>   
    </div>
  </div>
</div>

Answer 3

<div id="header-img">
    <div class="row justify-content-center align-self-center">
        <img class="card-img" src="https://www.w3schools.com/w3images/architect.jpg" alt="Card image">
           <div class="card-img-overlay">
              <h1 class="card-title"><span class="text-white">BR</span> Architects</h1>
           </div>
    </div>
</div>

Answer 4

顾名思义，text-center类仅使文本居中，您可能想使用align-items-center（用于垂直对齐）和/或justify-content-center（用于水平对齐）来居中其他类型的元素）。

官方文档中的更多信息： Vertical alignment Horizontal alignment

如何将元素垂直居中

4 个答案: