输入组
通过在文本输入、自定义选择和自定义文件输入两侧添加文本、按钮或按钮组,轻松扩展表单控件。
基本示例
在输入两侧放置一个附加组件或按钮。你也可以在输入两侧都放置一个。请记住将 <label>
放在输入组外部。
<div class="input-group mb-3">
<div class="input-group-prepend">
<span class="input-group-text" id="basic-addon1">@</span>
</div>
<input type="text" class="form-control" placeholder="Username" aria-label="Username" aria-describedby="basic-addon1">
</div>
<div class="input-group mb-3">
<input type="text" class="form-control" placeholder="Recipient's username" aria-label="Recipient's username" aria-describedby="basic-addon2">
<div class="input-group-append">
<span class="input-group-text" id="basic-addon2">@example.com</span>
</div>
</div>
<label for="basic-url">Your vanity URL</label>
<div class="input-group mb-3">
<div class="input-group-prepend">
<span class="input-group-text" id="basic-addon3">https://example.com/users/</span>
</div>
<input type="text" class="form-control" id="basic-url" aria-describedby="basic-addon3">
</div>
<div class="input-group mb-3">
<div class="input-group-prepend">
<span class="input-group-text">$</span>
</div>
<input type="text" class="form-control" aria-label="Amount (to the nearest dollar)">
<div class="input-group-append">
<span class="input-group-text">.00</span>
</div>
</div>
<div class="input-group">
<div class="input-group-prepend">
<span class="input-group-text">With textarea</span>
</div>
<textarea class="form-control" aria-label="With textarea"></textarea>
</div>
包裹
默认情况下,输入组通过 flex-wrap: wrap
进行包裹,以便在输入组中容纳自定义表单字段验证。你可以使用 .flex-nowrap
禁用此功能。
<div class="input-group flex-nowrap">
<div class="input-group-prepend">
<span class="input-group-text" id="addon-wrapping">@</span>
</div>
<input type="text" class="form-control" placeholder="Username" aria-label="Username" aria-describedby="addon-wrapping">
</div>
尺寸
将相对表单尺寸类添加到 .input-group
本身,其中的内容将自动调整大小,无需在每个元素上重复表单控件尺寸类。
不支持调整各个输入组元素的大小。
<div class="input-group input-group-sm mb-3">
<div class="input-group-prepend">
<span class="input-group-text" id="inputGroup-sizing-sm">Small</span>
</div>
<input type="text" class="form-control" aria-label="Sizing example input" aria-describedby="inputGroup-sizing-sm">
</div>
<div class="input-group mb-3">
<div class="input-group-prepend">
<span class="input-group-text" id="inputGroup-sizing-default">Default</span>
</div>
<input type="text" class="form-control" aria-label="Sizing example input" aria-describedby="inputGroup-sizing-default">
</div>
<div class="input-group input-group-lg">
<div class="input-group-prepend">
<span class="input-group-text" id="inputGroup-sizing-lg">Large</span>
</div>
<input type="text" class="form-control" aria-label="Sizing example input" aria-describedby="inputGroup-sizing-lg">
</div>
复选框和单选按钮
将任何复选框或单选按钮放在输入组的附加组件中,而不是文本中。
<div class="input-group mb-3">
<div class="input-group-prepend">
<div class="input-group-text">
<input type="checkbox" aria-label="Checkbox for following text input">
</div>
</div>
<input type="text" class="form-control" aria-label="Text input with checkbox">
</div>
<div class="input-group">
<div class="input-group-prepend">
<div class="input-group-text">
<input type="radio" aria-label="Radio button for following text input">
</div>
</div>
<input type="text" class="form-control" aria-label="Text input with radio button">
</div>
多个输入
虽然支持多个 <input>
,但验证样式仅适用于具有单个 <input>
的输入组。
<div class="input-group">
<div class="input-group-prepend">
<span class="input-group-text">First and last name</span>
</div>
<input type="text" aria-label="First name" class="form-control">
<input type="text" aria-label="Last name" class="form-control">
</div>
多个附加组件
支持多个附加组件,并且可以与复选框和单选按钮输入版本混合使用。
<div class="input-group mb-3">
<div class="input-group-prepend">
<span class="input-group-text">$</span>
<span class="input-group-text">0.00</span>
</div>
<input type="text" class="form-control" aria-label="Dollar amount (with dot and two decimal places)">
</div>
<div class="input-group">
<input type="text" class="form-control" aria-label="Dollar amount (with dot and two decimal places)">
<div class="input-group-append">
<span class="input-group-text">$</span>
<span class="input-group-text">0.00</span>
</div>
</div>
按钮附加组件
<div class="input-group mb-3">
<div class="input-group-prepend">
<button class="btn btn-outline-secondary" type="button" id="button-addon1">Button</button>
</div>
<input type="text" class="form-control" placeholder="" aria-label="Example text with button addon" aria-describedby="button-addon1">
</div>
<div class="input-group mb-3">
<input type="text" class="form-control" placeholder="Recipient's username" aria-label="Recipient's username" aria-describedby="button-addon2">
<div class="input-group-append">
<button class="btn btn-outline-secondary" type="button" id="button-addon2">Button</button>
</div>
</div>
<div class="input-group mb-3">
<div class="input-group-prepend" id="button-addon3">
<button class="btn btn-outline-secondary" type="button">Button</button>
<button class="btn btn-outline-secondary" type="button">Button</button>
</div>
<input type="text" class="form-control" placeholder="" aria-label="Example text with two button addons" aria-describedby="button-addon3">
</div>
<div class="input-group">
<input type="text" class="form-control" placeholder="Recipient's username" aria-label="Recipient's username with two button addons" aria-describedby="button-addon4">
<div class="input-group-append" id="button-addon4">
<button class="btn btn-outline-secondary" type="button">Button</button>
<button class="btn btn-outline-secondary" type="button">Button</button>
</div>
</div>
带下拉菜单的按钮
<div class="input-group mb-3">
<div class="input-group-prepend">
<button class="btn btn-outline-secondary dropdown-toggle" type="button" data-toggle="dropdown" aria-expanded="false">Dropdown</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div role="separator" class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div>
<input type="text" class="form-control" aria-label="Text input with dropdown button">
</div>
<div class="input-group">
<input type="text" class="form-control" aria-label="Text input with dropdown button">
<div class="input-group-append">
<button class="btn btn-outline-secondary dropdown-toggle" type="button" data-toggle="dropdown" aria-expanded="false">Dropdown</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div role="separator" class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div>
</div>
分段按钮
<div class="input-group mb-3">
<div class="input-group-prepend">
<button type="button" class="btn btn-outline-secondary">Action</button>
<button type="button" class="btn btn-outline-secondary dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div role="separator" class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div>
<input type="text" class="form-control" aria-label="Text input with segmented dropdown button">
</div>
<div class="input-group">
<input type="text" class="form-control" aria-label="Text input with segmented dropdown button">
<div class="input-group-append">
<button type="button" class="btn btn-outline-secondary">Action</button>
<button type="button" class="btn btn-outline-secondary dropdown-toggle dropdown-toggle-split" data-toggle="dropdown" aria-expanded="false">
<span class="sr-only">Toggle Dropdown</span>
</button>
<div class="dropdown-menu">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
<div role="separator" class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Separated link</a>
</div>
</div>
</div>
自定义表单
输入组包括对自定义选择和自定义文件输入的支持。不支持这些浏览器的默认版本。
自定义选择
<div class="input-group mb-3">
<div class="input-group-prepend">
<label class="input-group-text" for="inputGroupSelect01">Options</label>
</div>
<select class="custom-select" id="inputGroupSelect01">
<option selected>Choose...</option>
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
</select>
</div>
<div class="input-group mb-3">
<select class="custom-select" id="inputGroupSelect02">
<option selected>Choose...</option>
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
</select>
<div class="input-group-append">
<label class="input-group-text" for="inputGroupSelect02">Options</label>
</div>
</div>
<div class="input-group mb-3">
<div class="input-group-prepend">
<button class="btn btn-outline-secondary" type="button">Button</button>
</div>
<select class="custom-select" id="inputGroupSelect03" aria-label="Example select with button addon">
<option selected>Choose...</option>
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
</select>
</div>
<div class="input-group">
<select class="custom-select" id="inputGroupSelect04" aria-label="Example select with button addon">
<option selected>Choose...</option>
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
</select>
<div class="input-group-append">
<button class="btn btn-outline-secondary" type="button">Button</button>
</div>
</div>
自定义文件输入
<div class="input-group mb-3">
<div class="input-group-prepend">
<span class="input-group-text" id="inputGroupFileAddon01">Upload</span>
</div>
<div class="custom-file">
<input type="file" class="custom-file-input" id="inputGroupFile01" aria-describedby="inputGroupFileAddon01">
<label class="custom-file-label" for="inputGroupFile01">Choose file</label>
</div>
</div>
<div class="input-group mb-3">
<div class="custom-file">
<input type="file" class="custom-file-input" id="inputGroupFile02">
<label class="custom-file-label" for="inputGroupFile02" aria-describedby="inputGroupFileAddon02">Choose file</label>
</div>
<div class="input-group-append">
<span class="input-group-text" id="inputGroupFileAddon02">Upload</span>
</div>
</div>
<div class="input-group mb-3">
<div class="input-group-prepend">
<button class="btn btn-outline-secondary" type="button" id="inputGroupFileAddon03">Button</button>
</div>
<div class="custom-file">
<input type="file" class="custom-file-input" id="inputGroupFile03" aria-describedby="inputGroupFileAddon03">
<label class="custom-file-label" for="inputGroupFile03">Choose file</label>
</div>
</div>
<div class="input-group">
<div class="custom-file">
<input type="file" class="custom-file-input" id="inputGroupFile04" aria-describedby="inputGroupFileAddon04">
<label class="custom-file-label" for="inputGroupFile04">Choose file</label>
</div>
<div class="input-group-append">
<button class="btn btn-outline-secondary" type="button" id="inputGroupFileAddon04">Button</button>
</div>
</div>
辅助功能
确保所有表单控件都有适当的可访问名称,以便可以向辅助技术用户传达其用途。实现此目的最简单的方法是使用 <label>
元素,或者(对于按钮)将足够描述性的文本作为 <button>...</button>
内容的一部分包含在内。
对于无法包含可见的 <label>
或适当文本内容的情况,还有其他方式可以提供可访问的名称,例如
- 使用
.sr-only
类隐藏的<label>
元素 - 使用
aria-labelledby
指向可以作为标签的现有元素 - 提供
title
属性 - 使用
aria-label
明确设置元素的可访问名称
如果这些都不存在,辅助技术可能会使用 placeholder
属性作为 <input>
和 <textarea>
元素上可访问名称的备用选项。本部分中的示例提供了一些建议的特定案例方法。
虽然使用视觉隐藏内容(.sr-only
、aria-label
,甚至 placeholder
内容,一旦表单字段有内容,它就会消失)将使辅助技术用户受益,但对于某些用户来说,缺少可见标签文本仍然可能存在问题。某种形式的可见标签通常是最佳方法,既能满足可访问性,又能满足可用性。