Position定位

使用这些简写工具来快速配置元素的位置。

本页导航↓

Position 值

快速定位是可用的，尽管它们不响应。

<div class="position-static">...</div>
<div class="position-relative">...</div>
<div class="position-absolute">...</div>
<div class="position-fixed">...</div>
<div class="position-sticky">...</div>

元素排列

使用定位工具轻松排列元素。格式为 {property}-{position}.

其中属性为：

top - 为垂直顶部位置
start - 为水平左边位置 (在LTR里)
bottom - 为垂直底部位置
end - 为水平右边位置 (在LTR里)

其中的位置为：

0 - 0% 的边缘位置
50 - 50% 的边缘位置
100 - 100% 的边缘位置

(你可以通过向 $position-values Sass 映射变量添加条目来添加更多的位置值。)

<div class="position-relative">
  <div class="position-absolute top-0 start-0"></div>
  <div class="position-absolute top-0 end-0"></div>
  <div class="position-absolute top-50 start-50"></div>
  <div class="position-absolute bottom-50 end-50"></div>
  <div class="position-absolute bottom-0 start-0"></div>
  <div class="position-absolute bottom-0 end-0"></div>
</div>

居中元素

此外，您还可以使用转换实用工具 .translate-middle 类将元素居中。

这个类将 translateX(-50%) 和 translateY(-50%) 转换类应用到元素上，结合边缘定位实用工具，可以将元素绝对居中。

<div class="position-relative">
  <div class="position-absolute top-0 start-0 translate-middle"></div>
  <div class="position-absolute top-0 start-50 translate-middle"></div>
  <div class="position-absolute top-0 start-100 translate-middle"></div>
  <div class="position-absolute top-50 start-0 translate-middle"></div>
  <div class="position-absolute top-50 start-50 translate-middle"></div>
  <div class="position-absolute top-50 start-100 translate-middle"></div>
  <div class="position-absolute top-100 start-0 translate-middle"></div>
  <div class="position-absolute top-100 start-50 translate-middle"></div>
  <div class="position-absolute top-100 start-100 translate-middle"></div>
</div>

通过添加 .translate-middle-x 或 .translate-middle-y，使得元素只能在水平或垂直方向进行定位。

<div class="position-relative">
  <div class="position-absolute top-0 start-0"></div>
  <div class="position-absolute top-0 start-50 translate-middle-x"></div>
  <div class="position-absolute top-0 end-0"></div>
  <div class="position-absolute top-50 start-0 translate-middle-y"></div>
  <div class="position-absolute top-50 start-50 translate-middle"></div>
  <div class="position-absolute top-50 end-0 translate-middle-y"></div>
  <div class="position-absolute bottom-0 start-0"></div>
  <div class="position-absolute bottom-0 start-50 translate-middle-x"></div>
  <div class="position-absolute bottom-0 end-0"></div>
</div>

示例

以下是这些类的一些真实示例:

<button type="button" class="btn btn-primary position-relative">
  Mails <span class="position-absolute top-0 start-100 translate-middle badge rounded-pill bg-secondary">+99 <span class="visually-hidden">unread messages</span></span>
</button>

<button type="button" class="btn btn-dark position-relative">
  Marker <svg width="1em" height="1em" viewBox="0 0 16 16" class="position-absolute top-100 start-50 translate-middle mt-1 bi bi-caret-down-fill" fill="#212529" xmlns="http://www.w3.org/2000/svg"><path d="M7.247 11.14L2.451 5.658C1.885 5.013 2.345 4 3.204 4h9.592a1 1 0 0 1 .753 1.659l-4.796 5.48a1 1 0 0 1-1.506 0z"/></svg>
</button>

<button type="button" class="btn btn-primary position-relative">
  Alerts <span class="position-absolute top-0 start-100 translate-middle badge border border-light rounded-circle bg-danger p-2"><span class="visually-hidden">unread messages</span></span>
</button>

您可以将这些类与现有组件一起使用来创建新的组件。请记住，您可以通过向 $position-values 变量添加条目来扩展它的功能。

<div class="position-relative m-4">
  <div class="progress" style="height: 1px;">
    <div class="progress-bar" role="progressbar" style="width: 50%;" aria-valuenow="25" aria-valuemin="0" aria-valuemax="100"></div>
  </div>
  <button type="button" class="position-absolute top-0 start-0 translate-middle btn btn-sm btn-primary rounded-pill" style="width: 2rem; height:2rem;">1</button>
  <button type="button" class="position-absolute top-0 start-50 translate-middle btn btn-sm btn-primary rounded-pill" style="width: 2rem; height:2rem;">2</button>
  <button type="button" class="position-absolute top-0 start-100 translate-middle btn btn-sm btn-secondary rounded-pill" style="width: 2rem; height:2rem;">3</button>
</div>