按钮

使用 Bootstrap 的自定义按钮样式执行表单、对话框等中的操作，并支持多种尺寸、状态等。

基类

¥Base class

Bootstrap 有一个 .btn 基类，用于设置基本样式，例如填充和内容对齐。默认情况下，.btn 控件具有透明边框和背景颜色，并且缺乏任何明确的焦点和悬停样式。

¥Bootstrap has a base .btn class that sets up basic styles such as padding and content alignment. By default, .btn controls have a transparent border and background color, and lack any explicit focus and hover styles.

html

<button type="button" class="btn">Base class</button>

.btn 类旨在与我们的按钮变体结合使用，或作为你自己的自定义样式的基础。

¥The .btn class is intended to be used in conjunction with our button variants, or to serve as a basis for your own custom styles.

If you are using the .btn class on its own, remember to at least define some explicit :focus and/or :focus-visible styles.

变体

¥Variants

Bootstrap 包括几个按钮变体，每个变体都有自己的语义目的，并添加了一些额外的功能以实现更多控制。

¥Bootstrap includes several button variants, each serving its own semantic purpose, with a few extras thrown in for more control.

html

<button type="button" class="btn btn-primary">Primary</button>
<button type="button" class="btn btn-secondary">Secondary</button>
<button type="button" class="btn btn-success">Success</button>
<button type="button" class="btn btn-danger">Danger</button>
<button type="button" class="btn btn-warning">Warning</button>
<button type="button" class="btn btn-info">Info</button>
<button type="button" class="btn btn-light">Light</button>
<button type="button" class="btn btn-dark">Dark</button>

<button type="button" class="btn btn-link">Link</button>

Accessibility tip: Using color to add meaning only provides a visual indication, which will not be conveyed to users of assistive technologies like screen readers. Please ensure the meaning is obvious from the content itself (e.g., the visible text with a sufficient color contrast) or is included through alternative means, such as additional text hidden with the .visually-hidden class.

禁用文本换行

¥Disable text wrapping

如果你不希望按钮文本换行，可以将 .text-nowrap 类添加到按钮。在 Sass 中，你可以设置 $btn-white-space: nowrap 以禁用每个按钮的文本换行。

¥If you don’t want the button text to wrap, you can add the .text-nowrap class to the button. In Sass, you can set $btn-white-space: nowrap to disable text wrapping for each button.

按钮标签

¥Button tags

.btn 类设计为与 <button> 元素一起使用。但是，你也可以在 <a> 或 <input> 元素上使用这些类（尽管某些浏览器可能会应用略有不同的渲染）。

¥The .btn classes are designed to be used with the <button> element. However, you can also use these classes on <a> or <input> elements (though some browsers may apply a slightly different rendering).

当在 <a> 元素上使用用于触发页内功能（如折叠内容）的按钮类时，而不是链接到新页面或当前页面中的部分，这些链接应被赋予 role="button" 以适当地将其目的传达给辅助技术（例如屏幕阅读器）。

¥When using button classes on <a> elements that are used to trigger in-page functionality (like collapsing content), rather than linking to new pages or sections within the current page, these links should be given a role="button" to appropriately convey their purpose to assistive technologies such as screen readers.

Link

html

<a class="btn btn-primary" href="#" role="button">Link</a>
<button class="btn btn-primary" type="submit">Button</button>
<input class="btn btn-primary" type="button" value="Input">
<input class="btn btn-primary" type="submit" value="Submit">
<input class="btn btn-primary" type="reset" value="Reset">

轮廓按钮

¥Outline buttons

需要一个按钮，但不需要它们带来的大量背景颜色？将默认修饰符类替换为 .btn-outline-* 修饰符类，以删除任何按钮上的所有背景图片和颜色。

¥In need of a button, but not the hefty background colors they bring? Replace the default modifier classes with the .btn-outline-* ones to remove all background images and colors on any button.

html

<button type="button" class="btn btn-outline-primary">Primary</button>
<button type="button" class="btn btn-outline-secondary">Secondary</button>
<button type="button" class="btn btn-outline-success">Success</button>
<button type="button" class="btn btn-outline-danger">Danger</button>
<button type="button" class="btn btn-outline-warning">Warning</button>
<button type="button" class="btn btn-outline-info">Info</button>
<button type="button" class="btn btn-outline-light">Light</button>
<button type="button" class="btn btn-outline-dark">Dark</button>

Some of the button styles use a relatively light foreground color, and should only be used on a dark background in order to have sufficient contrast.

尺寸

¥Sizes

喜欢更大或更小的按钮吗？添加 .btn-lg 或 .btn-sm 以获取其他尺寸。

¥Fancy larger or smaller buttons? Add .btn-lg or .btn-sm for additional sizes.

html

<button type="button" class="btn btn-primary btn-lg">Large button</button>
<button type="button" class="btn btn-secondary btn-lg">Large button</button>

html

<button type="button" class="btn btn-primary btn-sm">Small button</button>
<button type="button" class="btn btn-secondary btn-sm">Small button</button>

你甚至可以使用 CSS 变量来调整自己的自定义大小：

¥You can even roll your own custom sizing with CSS variables:

html

<button type="button" class="btn btn-primary"
        style="--bs-btn-padding-y: .25rem; --bs-btn-padding-x: .5rem; --bs-btn-font-size: .75rem;">
  Custom button
</button>

禁用状态

¥Disabled state

通过将 disabled 布尔属性添加到任何 <button> 元素，使按钮看起来不活动。禁用的按钮应用了 pointer-events: none，以防止触发悬停和活动状态。

¥Make buttons look inactive by adding the disabled boolean attribute to any <button> element. Disabled buttons have pointer-events: none applied to, preventing hover and active states from triggering.

html

<button type="button" class="btn btn-primary" disabled>Primary button</button>
<button type="button" class="btn btn-secondary" disabled>Button</button>
<button type="button" class="btn btn-outline-primary" disabled>Primary button</button>
<button type="button" class="btn btn-outline-secondary" disabled>Button</button>

使用 <a> 元素的禁用按钮的行为有点不同：

¥Disabled buttons using the <a> element behave a bit different:

<a> 不支持 disabled 属性，因此你必须添加 .disabled 类以使其在视觉上显示为禁用。

¥<a>s don’t support the disabled attribute, so you must add the .disabled class to make it visually appear disabled.
其中包含一些面向未来的样式，以禁用锚按钮上的所有 pointer-events。

¥Some future-friendly styles are included to disable all pointer-events on anchor buttons.
使用 <a> 的禁用按钮应包含 aria-disabled="true" 属性，以向辅助技术指示元素的状态。

¥Disabled buttons using <a> should include the aria-disabled="true" attribute to indicate the state of the element to assistive technologies.
使用 <a> 的禁用按钮不应包含 href 属性。

¥Disabled buttons using <a> should not include the href attribute.

Primary link Link

html

<a class="btn btn-primary disabled" role="button" aria-disabled="true">Primary link</a>
<a class="btn btn-secondary disabled" role="button" aria-disabled="true">Link</a>

链接功能警告

¥Link functionality caveat

为了涵盖必须在禁用链接上保留 href 属性的情况，.disabled 类使用 pointer-events: none 来尝试禁用 <a> 的链接功能。请注意，此 CSS 属性尚未针对 HTML 进行标准化，但所有现代浏览器都支持它。此外，即使在支持 pointer-events: none 的浏览器中，键盘导航也不会受到影响，这意味着视力正常的键盘用户和辅助技术用户仍然能够激活这些链接。因此为了安全起见，除了 aria-disabled="true" 之外，还在这些链接上包含 tabindex="-1" 属性，以防止它们接收键盘焦点，并使用自定义 JavaScript 完全禁用它们的功能。

¥To cover cases where you have to keep the href attribute on a disabled link, the .disabled class uses pointer-events: none to try to disable the link functionality of <a>s. Note that this CSS property is not yet standardized for HTML, but all modern browsers support it. In addition, even in browsers that do support pointer-events: none, keyboard navigation remains unaffected, meaning that sighted keyboard users and users of assistive technologies will still be able to activate these links. So to be safe, in addition to aria-disabled="true", also include a tabindex="-1" attribute on these links to prevent them from receiving keyboard focus, and use custom JavaScript to disable their functionality altogether.

Primary link Link

html

<a href="#" class="btn btn-primary disabled" tabindex="-1" role="button" aria-disabled="true">Primary link</a>
<a href="#" class="btn btn-secondary disabled" tabindex="-1" role="button" aria-disabled="true">Link</a>

块按钮

¥Block buttons

结合我们的显示和间隙工具，创建全宽 “块按钮” 的响应式堆栈，就像 Bootstrap 4 中的堆栈一样。通过使用工具而不是特定于按钮的类，我们可以更好地控制间距、对齐和响应行为。

¥Create responsive stacks of full-width, “block buttons” like those in Bootstrap 4 with a mix of our display and gap utilities. By using utilities instead of button-specific classes, we have much greater control over spacing, alignment, and responsive behaviors.

html

<div class="d-grid gap-2">
  <button class="btn btn-primary" type="button">Button</button>
  <button class="btn btn-primary" type="button">Button</button>
</div>

在这里，我们创建了一个响应式变体，从垂直堆叠的按钮开始，直到 md 断点，其中 .d-md-block 替换了 .d-grid 类，从而使 gap-2 工具无效。调整浏览器大小以查看它们的变化。

¥Here we create a responsive variation, starting with vertically stacked buttons until the md breakpoint, where .d-md-block replaces the .d-grid class, thus nullifying the gap-2 utility. Resize your browser to see them change.

html

<div class="d-grid gap-2 d-md-block">
  <button class="btn btn-primary" type="button">Button</button>
  <button class="btn btn-primary" type="button">Button</button>
</div>

你可以使用网格列宽度类来调整块按钮的宽度。例如，对于半角 “阻止按钮”，请使用 .col-6。也将其与 .mx-auto 水平居中。

¥You can adjust the width of your block buttons with grid column width classes. For example, for a half-width “block button”, use .col-6. Center it horizontally with .mx-auto, too.

html

<div class="d-grid gap-2 col-6 mx-auto">
  <button class="btn btn-primary" type="button">Button</button>
  <button class="btn btn-primary" type="button">Button</button>
</div>

可以使用其他工具来调整水平按钮的对齐方式。在这里，我们采用了之前的响应式示例，并在按钮上添加了一些 Flex 工具和边距工具，以便在按钮不再堆叠时将按钮右对齐。

¥Additional utilities can be used to adjust the alignment of buttons when horizontal. Here we’ve taken our previous responsive example and added some flex utilities and a margin utility on the button to right-align the buttons when they’re no longer stacked.

html

<div class="d-grid gap-2 d-md-flex justify-content-md-end">
  <button class="btn btn-primary me-md-2" type="button">Button</button>
  <button class="btn btn-primary" type="button">Button</button>
</div>

按钮插件

¥Button plugin

按钮插件允许你创建简单的开/关切换按钮。

¥The button plugin allows you to create simple on/off toggle buttons.

Visually, these toggle buttons are identical to the checkbox toggle buttons. However, they are conveyed differently by assistive technologies: the checkbox toggles will be announced by screen readers as “checked”/“not checked” (since, despite their appearance, they are fundamentally still checkboxes), whereas these toggle buttons will be announced as “button”/“button pressed”. The choice between these two approaches will depend on the type of toggle you are creating, and whether or not the toggle will make sense to users when announced as a checkbox or as an actual button.

切换状态

¥Toggle states

添加 data-bs-toggle="button" 以切换按钮的 active 状态。如果你要预先切换按钮，则必须手动添加 .active 类和 aria-pressed="true" 以确保将其正确传达给辅助技术。

¥Add data-bs-toggle="button" to toggle a button’s active state. If you’re pre-toggling a button, you must manually add the .active class and aria-pressed="true" to ensure that it is conveyed appropriately to assistive technologies.

html

<p class="d-inline-flex gap-1">
  <button type="button" class="btn" data-bs-toggle="button">Toggle button</button>
  <button type="button" class="btn active" data-bs-toggle="button" aria-pressed="true">Active toggle button</button>
  <button type="button" class="btn" disabled data-bs-toggle="button">Disabled toggle button</button>
</p>
<p class="d-inline-flex gap-1">
  <button type="button" class="btn btn-primary" data-bs-toggle="button">Toggle button</button>
  <button type="button" class="btn btn-primary active" data-bs-toggle="button" aria-pressed="true">Active toggle button</button>
  <button type="button" class="btn btn-primary" disabled data-bs-toggle="button">Disabled toggle button</button>
</p>

Toggle link Active toggle link Disabled toggle link

html

<p class="d-inline-flex gap-1">
  <a href="#" class="btn" role="button" data-bs-toggle="button">Toggle link</a>
  <a href="#" class="btn active" role="button" data-bs-toggle="button" aria-pressed="true">Active toggle link</a>
  <a class="btn disabled" aria-disabled="true" role="button" data-bs-toggle="button">Disabled toggle link</a>
</p>
<p class="d-inline-flex gap-1">
  <a href="#" class="btn btn-primary" role="button" data-bs-toggle="button">Toggle link</a>
  <a href="#" class="btn btn-primary active" role="button" data-bs-toggle="button" aria-pressed="true">Active toggle link</a>
  <a class="btn btn-primary disabled" aria-disabled="true" role="button" data-bs-toggle="button">Disabled toggle link</a>
</p>

方法

¥Methods

你可以使用按钮构造函数创建按钮实例，例如：

¥You can create a button instance with the button constructor, for example:

const bsButton = new bootstrap.Button('#myButton')

Method	Description
`dispose`	Destroys an element’s button. (Removes stored data on the DOM element)
`getInstance`	Static method which allows you to get the button instance associated with a DOM element, you can use it like this: `bootstrap.Button.getInstance(element)`.
`getOrCreateInstance`	Static method which returns a button instance associated with a DOM element or creates a new one in case it wasn’t initialized. You can use it like this: `bootstrap.Button.getOrCreateInstance(element)`.
`toggle`	Toggles push state. Gives the button the appearance that it has been activated.

例如，切换所有按钮

¥For example, to toggle all buttons

document.querySelectorAll('.btn').forEach(buttonElement => {
  const button = bootstrap.Button.getOrCreateInstance(buttonElement)
  button.toggle()
})

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，按钮现在使用 .btn 上的本地 CSS 变量来增强实时自定义。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, buttons now use local CSS variables on .btn for enhanced real-time customization. Values for the CSS variables are set via Sass, so Sass customization is still supported, too.

scss/_buttons.scss

--#{$prefix}btn-padding-x: #{$btn-padding-x};
--#{$prefix}btn-padding-y: #{$btn-padding-y};
--#{$prefix}btn-font-family: #{$btn-font-family};
@include rfs($btn-font-size, --#{$prefix}btn-font-size);
--#{$prefix}btn-font-weight: #{$btn-font-weight};
--#{$prefix}btn-line-height: #{$btn-line-height};
--#{$prefix}btn-color: #{$btn-color};
--#{$prefix}btn-bg: transparent;
--#{$prefix}btn-border-width: #{$btn-border-width};
--#{$prefix}btn-border-color: transparent;
--#{$prefix}btn-border-radius: #{$btn-border-radius};
--#{$prefix}btn-hover-border-color: transparent;
--#{$prefix}btn-box-shadow: #{$btn-box-shadow};
--#{$prefix}btn-disabled-opacity: #{$btn-disabled-opacity};
--#{$prefix}btn-focus-box-shadow: 0 0 0 #{$btn-focus-width} rgba(var(--#{$prefix}btn-focus-shadow-rgb), .5);

每个 .btn-* 修饰符类都会更新适当的 CSS 变量，以最大限度地减少我们的 button-variant()、button-outline-variant() 和 button-size() mixin 的额外 CSS 规则。

¥Each .btn-* modifier class updates the appropriate CSS variables to minimize additional CSS rules with our button-variant(), button-outline-variant(), and button-size() mixins.

下面是构建自定义 .btn-* 修饰符类的示例，就像我们为文档特有的按钮所做的那样，通过使用我们自己的 CSS 和 Sass 变量的混合重新分配 Bootstrap 的 CSS 变量。

¥Here’s an example of building a custom .btn-* modifier class as we do for the buttons unique to our docs by reassigning Bootstrap’s CSS variables with a mixture of our own CSS and Sass variables.

site/assets/scss/_buttons.scss

.btn-bd-primary {
  --bs-btn-font-weight: 600;
  --bs-btn-color: var(--bs-white);
  --bs-btn-bg: var(--bd-violet-bg);
  --bs-btn-border-color: var(--bd-violet-bg);
  --bs-btn-hover-color: var(--bs-white);
  --bs-btn-hover-bg: #{shade-color($bd-violet, 10%)};
  --bs-btn-hover-border-color: #{shade-color($bd-violet, 10%)};
  --bs-btn-focus-shadow-rgb: var(--bd-violet-rgb);
  --bs-btn-active-color: var(--bs-btn-hover-color);
  --bs-btn-active-bg: #{shade-color($bd-violet, 20%)};
  --bs-btn-active-border-color: #{shade-color($bd-violet, 20%)};
}

Sass 变量

¥Sass variables

scss/_variables.scss

$btn-color:                   var(--#{$prefix}body-color);
$btn-padding-y:               $input-btn-padding-y;
$btn-padding-x:               $input-btn-padding-x;
$btn-font-family:             $input-btn-font-family;
$btn-font-size:               $input-btn-font-size;
$btn-line-height:             $input-btn-line-height;
$btn-white-space:             null; // Set to `nowrap` to prevent text wrapping

$btn-padding-y-sm:            $input-btn-padding-y-sm;
$btn-padding-x-sm:            $input-btn-padding-x-sm;
$btn-font-size-sm:            $input-btn-font-size-sm;

$btn-padding-y-lg:            $input-btn-padding-y-lg;
$btn-padding-x-lg:            $input-btn-padding-x-lg;
$btn-font-size-lg:            $input-btn-font-size-lg;

$btn-border-width:            $input-btn-border-width;

$btn-font-weight:             $font-weight-normal;
$btn-box-shadow:              inset 0 1px 0 rgba($white, .15), 0 1px 1px rgba($black, .075);
$btn-focus-width:             $input-btn-focus-width;
$btn-focus-box-shadow:        $input-btn-focus-box-shadow;
$btn-disabled-opacity:        .65;
$btn-active-box-shadow:       inset 0 3px 5px rgba($black, .125);

$btn-link-color:              var(--#{$prefix}link-color);
$btn-link-hover-color:        var(--#{$prefix}link-hover-color);
$btn-link-disabled-color:     $gray-600;
$btn-link-focus-shadow-rgb:   to-rgb(mix(color-contrast($link-color), $link-color, 15%));

// Allows for customizing button radius independently from global border radius
$btn-border-radius:           var(--#{$prefix}border-radius);
$btn-border-radius-sm:        var(--#{$prefix}border-radius-sm);
$btn-border-radius-lg:        var(--#{$prefix}border-radius-lg);

$btn-transition:              color .15s ease-in-out, background-color .15s ease-in-out, border-color .15s ease-in-out, box-shadow .15s ease-in-out;

$btn-hover-bg-shade-amount:       15%;
$btn-hover-bg-tint-amount:        15%;
$btn-hover-border-shade-amount:   20%;
$btn-hover-border-tint-amount:    10%;
$btn-active-bg-shade-amount:      20%;
$btn-active-bg-tint-amount:       20%;
$btn-active-border-shade-amount:  25%;
$btn-active-border-tint-amount:   10%;

Sass 混入

¥Sass mixins

按钮共有三种 mixin：按钮和按钮轮廓变体 mixin（均基于 $theme-colors），以及按钮大小 mixin。

¥There are three mixins for buttons: button and button outline variant mixins (both based on $theme-colors), plus a button size mixin.

scss/mixins/_buttons.scss

@mixin button-variant(
  $background,
  $border,
  $color: color-contrast($background),
  $hover-background: if($color == $color-contrast-light, shade-color($background, $btn-hover-bg-shade-amount), tint-color($background, $btn-hover-bg-tint-amount)),
  $hover-border: if($color == $color-contrast-light, shade-color($border, $btn-hover-border-shade-amount), tint-color($border, $btn-hover-border-tint-amount)),
  $hover-color: color-contrast($hover-background),
  $active-background: if($color == $color-contrast-light, shade-color($background, $btn-active-bg-shade-amount), tint-color($background, $btn-active-bg-tint-amount)),
  $active-border: if($color == $color-contrast-light, shade-color($border, $btn-active-border-shade-amount), tint-color($border, $btn-active-border-tint-amount)),
  $active-color: color-contrast($active-background),
  $disabled-background: $background,
  $disabled-border: $border,
  $disabled-color: color-contrast($disabled-background)
) {
  --#{$prefix}btn-color: #{$color};
  --#{$prefix}btn-bg: #{$background};
  --#{$prefix}btn-border-color: #{$border};
  --#{$prefix}btn-hover-color: #{$hover-color};
  --#{$prefix}btn-hover-bg: #{$hover-background};
  --#{$prefix}btn-hover-border-color: #{$hover-border};
  --#{$prefix}btn-focus-shadow-rgb: #{to-rgb(mix($color, $border, 15%))};
  --#{$prefix}btn-active-color: #{$active-color};
  --#{$prefix}btn-active-bg: #{$active-background};
  --#{$prefix}btn-active-border-color: #{$active-border};
  --#{$prefix}btn-active-shadow: #{$btn-active-box-shadow};
  --#{$prefix}btn-disabled-color: #{$disabled-color};
  --#{$prefix}btn-disabled-bg: #{$disabled-background};
  --#{$prefix}btn-disabled-border-color: #{$disabled-border};
}

scss/mixins/_buttons.scss

@mixin button-outline-variant(
  $color,
  $color-hover: color-contrast($color),
  $active-background: $color,
  $active-border: $color,
  $active-color: color-contrast($active-background)
) {
  --#{$prefix}btn-color: #{$color};
  --#{$prefix}btn-border-color: #{$color};
  --#{$prefix}btn-hover-color: #{$color-hover};
  --#{$prefix}btn-hover-bg: #{$active-background};
  --#{$prefix}btn-hover-border-color: #{$active-border};
  --#{$prefix}btn-focus-shadow-rgb: #{to-rgb($color)};
  --#{$prefix}btn-active-color: #{$active-color};
  --#{$prefix}btn-active-bg: #{$active-background};
  --#{$prefix}btn-active-border-color: #{$active-border};
  --#{$prefix}btn-active-shadow: #{$btn-active-box-shadow};
  --#{$prefix}btn-disabled-color: #{$color};
  --#{$prefix}btn-disabled-bg: transparent;
  --#{$prefix}btn-disabled-border-color: #{$color};
  --#{$prefix}gradient: none;
}

scss/mixins/_buttons.scss

@mixin button-size($padding-y, $padding-x, $font-size, $border-radius) {
  --#{$prefix}btn-padding-y: #{$padding-y};
  --#{$prefix}btn-padding-x: #{$padding-x};
  @include rfs($font-size, --#{$prefix}btn-font-size);
  --#{$prefix}btn-border-radius: #{$border-radius};
}

Sass 循环

¥Sass loops

按钮变体（对于常规按钮和轮廓按钮）使用它们各自的 mixins 和我们的 $theme-colors 映射来生成 scss/_buttons.scss 中的修饰符类。

¥Button variants (for regular and outline buttons) use their respective mixins with our $theme-colors map to generate the modifier classes in scss/_buttons.scss.

scss/_buttons.scss

@each $color, $value in $theme-colors {
  .btn-#{$color} {
    @if $color == "light" {
      @include button-variant(
        $value,
        $value,
        $hover-background: shade-color($value, $btn-hover-bg-shade-amount),
        $hover-border: shade-color($value, $btn-hover-border-shade-amount),
        $active-background: shade-color($value, $btn-active-bg-shade-amount),
        $active-border: shade-color($value, $btn-active-border-shade-amount)
      );
    } @else if $color == "dark" {
      @include button-variant(
        $value,
        $value,
        $hover-background: tint-color($value, $btn-hover-bg-tint-amount),
        $hover-border: tint-color($value, $btn-hover-border-tint-amount),
        $active-background: tint-color($value, $btn-active-bg-tint-amount),
        $active-border: tint-color($value, $btn-active-border-tint-amount)
      );
    } @else {
      @include button-variant($value, $value);
    }
  }
}

@each $color, $value in $theme-colors {
  .btn-outline-#{$color} {
    @include button-outline-variant($value);
  }
}