跳到主要内容 跳到文档导航

复选框和单选框

用我们完全重写的组件创建的跨浏览器和跨设备复选框和单选框。

方法

浏览器默认复选框和单选框被替换为.form-check,一系列用于两种输入类型的类改进了 HTML 元素的布局和行为,提供了更好的自定义和跨浏览器一致性。复选框用于选择列表中的一个或多个选项,而单选框用于从多个选项中选择一个。

在结构上,我们的<input><label>是兄弟元素,而不是<input>中的一个<label>。这稍微有点冗长,因为您必须指定idfor属性来关联<input><label>。我们对所有<input>状态使用兄弟选择器 (~) ,例如:checked:disabled。与.form-check-label类结合使用时,我们可以轻松地根据<input>的状态为每个项目设置文本样式。

我们的检查使用自定义 Bootstrap 图标来指示已检查或不确定状态。

复选框

HTML
<div class="form-check">
  <input class="form-check-input" type="checkbox" value="" id="flexCheckDefault">
  <label class="form-check-label" for="flexCheckDefault">
    Default checkbox
  </label>
</div>
<div class="form-check">
  <input class="form-check-input" type="checkbox" value="" id="flexCheckChecked" checked>
  <label class="form-check-label" for="flexCheckChecked">
    Checked checkbox
  </label>
</div>

不确定状态

当通过 JavaScript 手动设置时,复选框可以使用:indeterminate伪类(没有可用的 HTML 属性来指定它)。

HTML
<div class="form-check">
  <input class="form-check-input" type="checkbox" value="" id="flexCheckIndeterminate">
  <label class="form-check-label" for="flexCheckIndeterminate">
    Indeterminate checkbox
  </label>
</div>

禁用

添加disabled属性,关联的<label>会自动设置样式以匹配较浅的颜色,以帮助指示输入的状态。

HTML
<div class="form-check">
  <input class="form-check-input" type="checkbox" value="" id="flexCheckIndeterminateDisabled" disabled>
  <label class="form-check-label" for="flexCheckIndeterminateDisabled">
    Disabled indeterminate checkbox
  </label>
</div>
<div class="form-check">
  <input class="form-check-input" type="checkbox" value="" id="flexCheckDisabled" disabled>
  <label class="form-check-label" for="flexCheckDisabled">
    Disabled checkbox
  </label>
</div>
<div class="form-check">
  <input class="form-check-input" type="checkbox" value="" id="flexCheckCheckedDisabled" checked disabled>
  <label class="form-check-label" for="flexCheckCheckedDisabled">
    Disabled checked checkbox
  </label>
</div>

单选框

HTML
<div class="form-check">
  <input class="form-check-input" type="radio" name="flexRadioDefault" id="flexRadioDefault1">
  <label class="form-check-label" for="flexRadioDefault1">
    Default radio
  </label>
</div>
<div class="form-check">
  <input class="form-check-input" type="radio" name="flexRadioDefault" id="flexRadioDefault2" checked>
  <label class="form-check-label" for="flexRadioDefault2">
    Default checked radio
  </label>
</div>

禁用

添加disabled属性,关联的<label>会自动设置样式以匹配较浅的颜色,以帮助指示输入的状态。

HTML
<div class="form-check">
  <input class="form-check-input" type="radio" name="flexRadioDisabled" id="flexRadioDisabled" disabled>
  <label class="form-check-label" for="flexRadioDisabled">
    Disabled radio
  </label>
</div>
<div class="form-check">
  <input class="form-check-input" type="radio" name="flexRadioDisabled" id="flexRadioCheckedDisabled" checked disabled>
  <label class="form-check-label" for="flexRadioCheckedDisabled">
    Disabled checked radio
  </label>
</div>

Switch开关

开关具有自定义复选框的标记,但使用.form-switch类来呈现切换开关。考虑使用role="switch"以更准确地将控制的性质传达给支持此元素的辅助技术。在较旧的辅助技术中,它只会被宣布为常规复选框作为后备。Switch开关也支持该disabled属性。

HTML
<div class="form-check form-switch">
  <input class="form-check-input" type="checkbox" role="switch" id="flexSwitchCheckDefault">
  <label class="form-check-label" for="flexSwitchCheckDefault">Default switch checkbox input</label>
</div>
<div class="form-check form-switch">
  <input class="form-check-input" type="checkbox" role="switch" id="flexSwitchCheckChecked" checked>
  <label class="form-check-label" for="flexSwitchCheckChecked">Checked switch checkbox input</label>
</div>
<div class="form-check form-switch">
  <input class="form-check-input" type="checkbox" role="switch" id="flexSwitchCheckDisabled" disabled>
  <label class="form-check-label" for="flexSwitchCheckDisabled">Disabled switch checkbox input</label>
</div>
<div class="form-check form-switch">
  <input class="form-check-input" type="checkbox" role="switch" id="flexSwitchCheckCheckedDisabled" checked disabled>
  <label class="form-check-label" for="flexSwitchCheckCheckedDisabled">Disabled checked switch checkbox input</label>
</div>

默认布局

默认情况下,使用.form-check,任何数量的直接兄弟复选框和单选按钮将垂直堆叠并调整适当间隔。

HTML
<div class="form-check">
  <input class="form-check-input" type="checkbox" value="" id="defaultCheck1">
  <label class="form-check-label" for="defaultCheck1">
    Default checkbox
  </label>
</div>
<div class="form-check">
  <input class="form-check-input" type="checkbox" value="" id="defaultCheck2" disabled>
  <label class="form-check-label" for="defaultCheck2">
    Disabled checkbox
  </label>
</div>
HTML
<div class="form-check">
  <input class="form-check-input" type="radio" name="exampleRadios" id="exampleRadios1" value="option1" checked>
  <label class="form-check-label" for="exampleRadios1">
    Default radio
  </label>
</div>
<div class="form-check">
  <input class="form-check-input" type="radio" name="exampleRadios" id="exampleRadios2" value="option2">
  <label class="form-check-label" for="exampleRadios2">
    Second default radio
  </label>
</div>
<div class="form-check">
  <input class="form-check-input" type="radio" name="exampleRadios" id="exampleRadios3" value="option3" disabled>
  <label class="form-check-label" for="exampleRadios3">
    Disabled radio
  </label>
</div>

Inline布局

通过添加.form-check-inline.form-check将复选框或单选框分组在同一水平行上。

HTML
<div class="form-check form-check-inline">
  <input class="form-check-input" type="checkbox" id="inlineCheckbox1" value="option1">
  <label class="form-check-label" for="inlineCheckbox1">1</label>
</div>
<div class="form-check form-check-inline">
  <input class="form-check-input" type="checkbox" id="inlineCheckbox2" value="option2">
  <label class="form-check-label" for="inlineCheckbox2">2</label>
</div>
<div class="form-check form-check-inline">
  <input class="form-check-input" type="checkbox" id="inlineCheckbox3" value="option3" disabled>
  <label class="form-check-label" for="inlineCheckbox3">3 (disabled)</label>
</div>
HTML
<div class="form-check form-check-inline">
  <input class="form-check-input" type="radio" name="inlineRadioOptions" id="inlineRadio1" value="option1">
  <label class="form-check-label" for="inlineRadio1">1</label>
</div>
<div class="form-check form-check-inline">
  <input class="form-check-input" type="radio" name="inlineRadioOptions" id="inlineRadio2" value="option2">
  <label class="form-check-label" for="inlineRadio2">2</label>
</div>
<div class="form-check form-check-inline">
  <input class="form-check-input" type="radio" name="inlineRadioOptions" id="inlineRadio3" value="option3" disabled>
  <label class="form-check-label" for="inlineRadio3">3 (disabled)</label>
</div>

反转布局

添加.form-check-reverse将复选框、单选框和开关放在另一侧。

HTML
<div class="form-check form-check-reverse">
  <input class="form-check-input" type="checkbox" value="" id="reverseCheck1">
  <label class="form-check-label" for="reverseCheck1">
    Reverse checkbox
  </label>
</div>
<div class="form-check form-check-reverse">
  <input class="form-check-input" type="checkbox" value="" id="reverseCheck2" disabled>
  <label class="form-check-label" for="reverseCheck2">
    Disabled reverse checkbox
  </label>
</div>

<div class="form-check form-switch form-check-reverse">
  <input class="form-check-input" type="checkbox" id="flexSwitchCheckReverse">
  <label class="form-check-label" for="flexSwitchCheckReverse">Reverse switch checkbox input</label>
</div>

无文本标签

省略了.form-check没有标签文本的复选框和单选框。请记住仍然为辅助技术提供某种形式的可访问名称(例如,用aria-label)。有关详细信息,请参阅表单概述可访问性部分。

HTML
<div>
  <input class="form-check-input" type="checkbox" id="checkboxNoLabel" value="" aria-label="...">
</div>

<div>
  <input class="form-check-input" type="radio" name="radioNoLabel" id="radioNoLabel1" value="" aria-label="...">
</div>

切换按钮

通过使用.btn样式在<label>元素上创建类似按钮的复选框和单选按钮。如果需要,可以将这些切换按钮进一步分组到一个按钮组中。

复选框切换按钮

HTML
<input type="checkbox" class="btn-check" id="btn-check" autocomplete="off">
<label class="btn btn-primary" for="btn-check">Single toggle</label>
HTML
<input type="checkbox" class="btn-check" id="btn-check-2" checked autocomplete="off">
<label class="btn btn-primary" for="btn-check-2">Checked</label>
HTML
<input type="checkbox" class="btn-check" id="btn-check-3" autocomplete="off" disabled>
<label class="btn btn-primary" for="btn-check-3">Disabled</label>
在视觉上,这些复选框切换按钮与按钮插件切换按钮相同。然而,它们通过辅助技术以不同的方式传达:屏幕阅读器将宣布复选框切换为“已选中”/“未选中”(因为,尽管它们的外观,它们基本上仍然是复选框),而按钮插件切换按钮将是宣布为“按钮”/“按下按钮”。这两种方法之间的选择将取决于您正在创建的切换类型,以及切换作为复选框或实际按钮宣布时对用户是否有意义。

单选按钮

HTML
<input type="radio" class="btn-check" name="options" id="option1" autocomplete="off" checked>
<label class="btn btn-secondary" for="option1">Checked</label>

<input type="radio" class="btn-check" name="options" id="option2" autocomplete="off">
<label class="btn btn-secondary" for="option2">Radio</label>

<input type="radio" class="btn-check" name="options" id="option3" autocomplete="off" disabled>
<label class="btn btn-secondary" for="option3">Disabled</label>

<input type="radio" class="btn-check" name="options" id="option4" autocomplete="off">
<label class="btn btn-secondary" for="option4">Radio</label>

轮廓样式

支持.btn的不同变体,例如各种轮廓样式。



HTML
<input type="checkbox" class="btn-check" id="btn-check-outlined" autocomplete="off">
<label class="btn btn-outline-primary" for="btn-check-outlined">Single toggle</label><br>

<input type="checkbox" class="btn-check" id="btn-check-2-outlined" checked autocomplete="off">
<label class="btn btn-outline-secondary" for="btn-check-2-outlined">Checked</label><br>

<input type="radio" class="btn-check" name="options-outlined" id="success-outlined" autocomplete="off" checked>
<label class="btn btn-outline-success" for="success-outlined">Checked success radio</label>

<input type="radio" class="btn-check" name="options-outlined" id="danger-outlined" autocomplete="off">
<label class="btn btn-outline-danger" for="danger-outlined">Danger radio</label>

Sass

变量

检查变量:

$form-check-input-width:                  1em;
$form-check-min-height:                   $font-size-base * $line-height-base;
$form-check-padding-start:                $form-check-input-width + .5em;
$form-check-margin-bottom:                .125rem;
$form-check-label-color:                  null;
$form-check-label-cursor:                 null;
$form-check-transition:                   null;

$form-check-input-active-filter:          brightness(90%);

$form-check-input-bg:                     $input-bg;
$form-check-input-border:                 var(--#{$prefix}border-width) solid var(--#{$prefix}border-color);
$form-check-input-border-radius:          .25em;
$form-check-radio-border-radius:          50%;
$form-check-input-focus-border:           $input-focus-border-color;
$form-check-input-focus-box-shadow:       $input-btn-focus-box-shadow;

$form-check-input-checked-color:          $component-active-color;
$form-check-input-checked-bg-color:       $component-active-bg;
$form-check-input-checked-border-color:   $form-check-input-checked-bg-color;
$form-check-input-checked-bg-image:       url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 20 20'><path fill='none' stroke='#{$form-check-input-checked-color}' stroke-linecap='round' stroke-linejoin='round' stroke-width='3' d='m6 10 3 3 6-6'/></svg>");
$form-check-radio-checked-bg-image:       url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='-4 -4 8 8'><circle r='2' fill='#{$form-check-input-checked-color}'/></svg>");

$form-check-input-indeterminate-color:          $component-active-color;
$form-check-input-indeterminate-bg-color:       $component-active-bg;
$form-check-input-indeterminate-border-color:   $form-check-input-indeterminate-bg-color;
$form-check-input-indeterminate-bg-image:       url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 20 20'><path fill='none' stroke='#{$form-check-input-indeterminate-color}' stroke-linecap='round' stroke-linejoin='round' stroke-width='3' d='M6 10h8'/></svg>");

$form-check-input-disabled-opacity:        .5;
$form-check-label-disabled-opacity:        $form-check-input-disabled-opacity;
$form-check-btn-check-disabled-opacity:    $btn-disabled-opacity;

$form-check-inline-margin-end:    1rem;

开关变量:

$form-switch-color:               rgba($black, .25);
$form-switch-width:               2em;
$form-switch-padding-start:       $form-switch-width + .5em;
$form-switch-bg-image:            url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='-4 -4 8 8'><circle r='3' fill='#{$form-switch-color}'/></svg>");
$form-switch-border-radius:       $form-switch-width;
$form-switch-transition:          background-position .15s ease-in-out;

$form-switch-focus-color:         $input-focus-border-color;
$form-switch-focus-bg-image:      url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='-4 -4 8 8'><circle r='3' fill='#{$form-switch-focus-color}'/></svg>");

$form-switch-checked-color:       $component-active-color;
$form-switch-checked-bg-image:    url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='-4 -4 8 8'><circle r='3' fill='#{$form-switch-checked-color}'/></svg>");
$form-switch-checked-bg-position: right center;