添加样式以动态更改其宽度后如何垂直居中 Bootstrap 模态？答案

【问题标题】：How to vertically center Bootstrap modal after adding style to dynamically change its width?添加样式以动态更改其宽度后如何垂直居中 Bootstrap 模态？
【发布时间】：2022-11-22 21:04:57
【问题描述】：

我需要增加 Bootstrap 模态宽度，所以我使用了这篇文章中的代码：How to resize Twitter Bootstrap modal dynamically based on the content

.modal-dialog{
    position: relative;
    display: table; /* This is important */ 
    overflow-y: auto;    
    overflow-x: auto;
    width: auto;
    min-width: 300px;   
}

但是现在我的模式不是垂直居中的。

编辑：我已经有 modal-dialog-centered 但它坏了

我尝试用带有 d-flex align-items-center 的 div 包装 modal-content 但这也不起作用：

<div class="modal" tabindex="-1" role="dialog">
  <div class="modal-dialog modal-dialog-centered" role="document">
    <div class="d-flex align-items-center">
      <div class="modal-content">
        <div class="modal-header">
          <h5 class="modal-title">Modal title</h5>
          <button type="button" class="close" data-dismiss="modal" aria-label="Close">
            <span aria-hidden="true">&times;</span>
          </button>
        </div>
        <div class="modal-body">
          <p>Modal body text goes here.</p>
        </div>
        <div class="modal-footer">
          <button type="button" class="btn btn-primary">Save changes 
 </button>
          <button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button>
        </div>
      </div>
    </div>
  </div>
</div>

但这也不管用

【问题讨论】：

标签： css twitter-bootstrap bootstrap-4

【解决方案1】：

只需添加 Bootstrap 类 modal-dialog-centered。

请参见下面的 sn-p。

.modal-dialog {
  position: relative;
  display: table; /* This is important */
  overflow-y: auto;
  overflow-x: auto;
  width: auto;
  min-width: 300px;
}

<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@4.6.2/dist/css/bootstrap.min.css" integrity="sha384-xOolHFLEh07PJGoPkLv1IbcEPTNtaed2xpHsD9ESMhqIYd0nLMwNLD69Npy4HI+N" crossorigin="anonymous">
<script src="https://cdn.jsdelivr.net/npm/jquery@3.5.1/dist/jquery.slim.min.js" integrity="sha384-DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/bootstrap@4.6.2/dist/js/bootstrap.bundle.min.js" integrity="sha384-Fy6S3B9q64WdZWQUiU+q4/2Lc9npb8tCaSX9FK7E8HnRr0Jz8D6OP9dO5Vg3Q9ct" crossorigin="anonymous"></script>

<button type="button" class="btn btn-primary" data-toggle="modal" data-target="#exampleModal">
  Launch demo modal
</button>

<div class="modal" role="dialog" id="exampleModal" tabindex="-1" aria-labelledby="exampleModalLabel" aria-hidden="true">
  <div class="modal-dialog modal-dialog-centered" role="document">
    <div class="d-flex align-items-center">
      <div class="modal-content">
        <div class="modal-header">
          <h5 class="modal-title">Modal title</h5>
          <button type="button" class="close" data-dismiss="modal" aria-label="Close">
            <span aria-hidden="true">&times;</span>
          </button>
        </div>
        <div class="modal-body">
          <p>Modal body text goes here.</p>
        </div>
        <div class="modal-footer">
          <button type="button" class="btn btn-primary">Save changes 
 </button>
          <button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button>
        </div>
      </div>
    </div>
  </div>
</div>

编辑

.modal-dialog {
  position: relative;
  display: table;
  overflow-y: auto;
  overflow-x: auto;
  width: auto;
  min-width: 300px;
  
  /* Added */
  height: 100%;
  display: flex;
  margin-top: 0 !important;
}

<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@4.6.2/dist/css/bootstrap.min.css" integrity="sha384-xOolHFLEh07PJGoPkLv1IbcEPTNtaed2xpHsD9ESMhqIYd0nLMwNLD69Npy4HI+N" crossorigin="anonymous">
<script src="https://cdn.jsdelivr.net/npm/jquery@3.5.1/dist/jquery.slim.min.js" integrity="sha384-DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/bootstrap@4.6.2/dist/js/bootstrap.bundle.min.js" integrity="sha384-Fy6S3B9q64WdZWQUiU+q4/2Lc9npb8tCaSX9FK7E8HnRr0Jz8D6OP9dO5Vg3Q9ct" crossorigin="anonymous"></script>

<button type="button" class="btn btn-primary" data-toggle="modal" data-target="#exampleModal">
  Launch demo modal
</button>

<div class="modal" role="dialog" id="exampleModal" tabindex="-1" aria-labelledby="exampleModalLabel" aria-hidden="true">
  <div class="modal-dialog" role="document">
    <div class="d-flex align-items-center">
      <div class="modal-content">
        <div class="modal-header">
          <h5 class="modal-title">Modal title</h5>
          <button type="button" class="close" data-dismiss="modal" aria-label="Close">
            <span aria-hidden="true">&times;</span>
          </button>
        </div>
        <div class="modal-body">
          <p>Modal body text goes here.</p>
        </div>
        <div class="modal-footer">
          <button type="button" class="btn btn-primary">Save changes 
 </button>
          <button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button>
        </div>
      </div>
    </div>
  </div>
</div>

【讨论】：

抱歉忘了说我已经有 modal-dialog-centered 但在添加自定义 css 后它坏了 - 更新了帖子
我编辑了我的答案。