面包屑

通过 CSS 自动添加分隔符，指示当前页面在导航层次结构中的位置。

示例

¥Example

使用带有链接列表项的有序或无序列表来创建最小样式的面包屑。使用我们的工具根据需要添加其他样式。

¥Use an ordered or unordered list with linked list items to create a minimally styled breadcrumb. Use our utilities to add additional styles as desired.

html

<nav aria-label="breadcrumb">
  <ol class="breadcrumb">
    <li class="breadcrumb-item active" aria-current="page">Home</li>
  </ol>
</nav>

<nav aria-label="breadcrumb">
  <ol class="breadcrumb">
    <li class="breadcrumb-item"><a href="#">Home</a></li>
    <li class="breadcrumb-item active" aria-current="page">Library</li>
  </ol>
</nav>

<nav aria-label="breadcrumb">
  <ol class="breadcrumb">
    <li class="breadcrumb-item"><a href="#">Home</a></li>
    <li class="breadcrumb-item"><a href="#">Library</a></li>
    <li class="breadcrumb-item active" aria-current="page">Data</li>
  </ol>
</nav>

分隔线

¥Dividers

分隔符通过 ::before 和 content 自动添加到 CSS 中。可以通过修改本地 CSS 自定义属性 --bs-breadcrumb-divider 或通过 $breadcrumb-divider Sass 变量以及 $breadcrumb-divider-flipped（如果需要）对其 RTL 对应项进行更改。我们默认使用 Sass 变量，该变量被设置为自定义属性的后备。这样，你就可以获得一个全局分隔符，你可以随时覆盖该分隔符，而无需重新编译 CSS。

¥Dividers are automatically added in CSS through ::before and content. They can be changed by modifying a local CSS custom property --bs-breadcrumb-divider, or through the $breadcrumb-divider Sass variable — and $breadcrumb-divider-flipped for its RTL counterpart, if needed. We default to our Sass variable, which is set as a fallback to the custom property. This way, you get a global divider that you can override without recompiling CSS at any time.

html

<nav style="--bs-breadcrumb-divider: '>';" aria-label="breadcrumb">
  <ol class="breadcrumb">
    <li class="breadcrumb-item"><a href="#">Home</a></li>
    <li class="breadcrumb-item active" aria-current="page">Library</li>
  </ol>
</nav>

通过 Sass 修改时，需要使用 quote 函数来生成字符串周围的引号。例如，使用 > 作为分隔符，你可以这样使用：

¥When modifying via Sass, the quote function is required to generate the quotes around a string. For example, using > as the divider, you can use this:

$breadcrumb-divider: quote(">");

也可以使用嵌入式 SVG 图标。通过我们的 CSS 自定义属性应用它，或使用 Sass 变量。

¥It’s also possible to use an embedded SVG icon. Apply it via our CSS custom property, or use the Sass variable.

内联 SVG 需要正确转义的字符。部分保留字符，例如 <、> 和 #，必须进行 URL 编码或转义。我们使用 escape-svg() Sass 函数函数对 $breadcrumb-divider 变量进行上述操作。自定义 CSS 变量时，你必须自行处理。阅读 Kevin Weber 在 CodePen 上的讲解了解更多信息。

¥Inlined SVG requires properly escaped characters. Some reserved characters, such as <, > and #, must be URL-encoded or escaped. We do this with the $breadcrumb-divider variable using our escape-svg() Sass function. When customizing the CSS variable, you must handle this yourself. Read Kevin Weber’s explanations on CodePen for more info.

html

<nav style="--bs-breadcrumb-divider: url(&#34;data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='8' height='8'%3E%3Cpath d='M2.5 0L1 1.5 3.5 4 1 6.5 2.5 8l4-4-4-4z' fill='%236c757d'/%3E%3C/svg%3E&#34;);" aria-label="breadcrumb">
  <ol class="breadcrumb">
    <li class="breadcrumb-item"><a href="#">Home</a></li>
    <li class="breadcrumb-item active" aria-current="page">Library</li>
  </ol>
</nav>

$breadcrumb-divider: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' width='8' height='8'><path d='M2.5 0L1 1.5 3.5 4 1 6.5 2.5 8l4-4-4-4z' fill='#{$breadcrumb-divider-color}'/></svg>");

你还可以删除分隔符设置 --bs-breadcrumb-divider: '';（CSS 自定义属性中的空字符串算作一个值），或将 Sass 变量设置为 $breadcrumb-divider: none;。

¥You can also remove the divider setting --bs-breadcrumb-divider: ''; (empty strings in CSS custom properties counts as a value), or setting the Sass variable to $breadcrumb-divider: none;.

html

<nav style="--bs-breadcrumb-divider: '';" aria-label="breadcrumb">
  <ol class="breadcrumb">
    <li class="breadcrumb-item"><a href="#">Home</a></li>
    <li class="breadcrumb-item active" aria-current="page">Library</li>
  </ol>
</nav>

$breadcrumb-divider: none;

无障碍

¥Accessibility

由于面包屑导航提供导航功能，因此最好添加一个有意义的标签（例如 aria-label="breadcrumb"）来描述 <nav> 元素中提供的导航类型，并在集合的最后一项上应用 aria-current="page" 以指示它代表当前页面。

¥Since breadcrumbs provide a navigation, it’s a good idea to add a meaningful label such as aria-label="breadcrumb" to describe the type of navigation provided in the <nav> element, as well as applying an aria-current="page" to the last item of the set to indicate that it represents the current page.

有关详细信息，请参阅 ARIA 创作实践指南面包屑模式。

¥For more information, see the ARIA Authoring Practices Guide breadcrumb pattern.

CSS

变量

¥Variables

Added in v5.2.0

作为 Bootstrap 不断发展的 CSS 变量方法的一部分，面包屑导航现在在 .breadcrumb 上使用本地 CSS 变量来增强实时自定义功能。CSS 变量的值是通过 Sass 设置的，因此仍然支持 Sass 自定义。

¥As part of Bootstrap’s evolving CSS variables approach, breadcrumbs now use local CSS variables on .breadcrumb for enhanced real-time customization. Values for the CSS variables are set via Sass, so Sass customization is still supported, too.

scss/_breadcrumb.scss

--#{$prefix}breadcrumb-padding-x: #{$breadcrumb-padding-x};
--#{$prefix}breadcrumb-padding-y: #{$breadcrumb-padding-y};
--#{$prefix}breadcrumb-margin-bottom: #{$breadcrumb-margin-bottom};
@include rfs($breadcrumb-font-size, --#{$prefix}breadcrumb-font-size);
--#{$prefix}breadcrumb-bg: #{$breadcrumb-bg};
--#{$prefix}breadcrumb-border-radius: #{$breadcrumb-border-radius};
--#{$prefix}breadcrumb-divider-color: #{$breadcrumb-divider-color};
--#{$prefix}breadcrumb-item-padding-x: #{$breadcrumb-item-padding-x};
--#{$prefix}breadcrumb-item-active-color: #{$breadcrumb-active-color};

Sass 变量

¥Sass variables

scss/_variables.scss

$breadcrumb-font-size:              null;
$breadcrumb-padding-y:              0;
$breadcrumb-padding-x:              0;
$breadcrumb-item-padding-x:         .5rem;
$breadcrumb-margin-bottom:          1rem;
$breadcrumb-bg:                     null;
$breadcrumb-divider-color:          var(--#{$prefix}secondary-color);
$breadcrumb-active-color:           var(--#{$prefix}secondary-color);
$breadcrumb-divider:                quote("/");
$breadcrumb-divider-flipped:        $breadcrumb-divider;
$breadcrumb-border-radius:          null;