输入组（Input group）
通过在文本输入、自定义选择和自定义文件输入的任一侧添加文本、按钮或按钮组，可以轻松扩展表单控件。
在本页面
基本示例
在输入的任一侧放置一个附加组件或按钮。也可以在输入的两侧放置一个。 记住将<label>放在输入组之外。
@
@example.com
https://example.com/users/
$
.00
@
With textarea
<div class="input-group mb-3">
<span class="input-group-text" id="basic-addon1">@</span>
<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">
<span class="input-group-text" id="basic-addon2">@example.com</span>
</div>
<label for="basic-url" class="form-label">Your vanity URL</label>
<div class="input-group mb-3">
<span class="input-group-text" id="basic-addon3">https://example.com/users/</span>
<input type="text" class="form-control" id="basic-url" aria-describedby="basic-addon3">
</div>
<div class="input-group mb-3">
<span class="input-group-text">$</span>
<input type="text" class="form-control" aria-label="Amount (to the nearest dollar)">
<span class="input-group-text">.00</span>
</div>
<div class="input-group mb-3">
<input type="text" class="form-control" placeholder="Username" aria-label="Username">
<span class="input-group-text">@</span>
<input type="text" class="form-control" placeholder="Server" aria-label="Server">
</div>
<div class="input-group">
<span class="input-group-text">With textarea</span>
<textarea class="form-control" aria-label="With textarea"></textarea>
</div>包装（Wrapping）
默认情况下，输入组通过flex-wrap: wrap进行包装，以便在输入组中容纳自定义表单字段验证。您可以使用.flex-nowrap禁用此功能。
@
<div class="input-group flex-nowrap">
<span class="input-group-text" id="addon-wrapping">@</span>
<input type="text" class="form-control" placeholder="Username" aria-label="Username" aria-describedby="addon-wrapping">
</div>调整大小
将相关表单大小调整类添加到.input-group本身，并且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大小调整类。
不支持对单个输入组元素进行大小调整。
Small
Default
Large
<div class="input-group input-group-sm mb-3">
<span class="input-group-text" id="inputGroup-sizing-sm">Small</span>
<input type="text" class="form-control" aria-label="Sizing example input" aria-describedby="inputGroup-sizing-sm">
</div>
<div class="input-group mb-3">
<span class="input-group-text" id="inputGroup-sizing-default">Default</span>
<input type="text" class="form-control" aria-label="Sizing example input" aria-describedby="inputGroup-sizing-default">
</div>
<div class="input-group input-group-lg">
<span class="input-group-text" id="inputGroup-sizing-lg">Large</span>
<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选项放置在输入组的加载项中，而不是文本中。
<div class="input-group mb-3">
<div class="input-group-text">
<input class="form-check-input" type="checkbox" value="" aria-label="Checkbox for following text input">
</div>
<input type="text" class="form-control" aria-label="Text input with checkbox">
</div>
<div class="input-group">
<div class="input-group-text">
<input class="form-check-input" type="radio" value="" aria-label="Radio button for following text input">
</div>
<input type="text" class="form-control" aria-label="Text input with radio button">
</div>多个输入
虽然视觉上支持多个<input>，但验证样式仅适用于具有单个<input>的输入组。
First and last name
<div class="input-group">
<span class="input-group-text">First and last name</span>
<input type="text" aria-label="First name" class="form-control">
<input type="text" aria-label="Last name" class="form-control">
</div>多个插件
支持多个加载项，可以与复选框和单选输入版本混合使用。
$
0.00
$
0.00
<div class="input-group mb-3">
<span class="input-group-text">$</span>
<span class="input-group-text">0.00</span>
<input type="text" class="form-control" aria-label="Dollar amount (with dot and two decimal places)">
</div>
<div class="input-group">
<input type="text" class="form-control" aria-label="Dollar amount (with dot and two decimal places)">
<span class="input-group-text">$</span>
<span class="input-group-text">0.00</span>
</div>按钮插件
<div class="input-group mb-3">
<button class="btn btn-outline-secondary" type="button" id="button-addon1">Button</button>
<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">
<button class="btn btn-outline-secondary" type="button" id="button-addon2">Button</button>
</div>
<div class="input-group mb-3">
<button class="btn btn-outline-secondary" type="button">Button</button>
<button class="btn btn-outline-secondary" type="button">Button</button>
<input type="text" class="form-control" placeholder="" aria-label="Example text with two button addons">
</div>
<div class="input-group">
<input type="text" class="form-control" placeholder="Recipient's username" aria-label="Recipient's username with two button addons">
<button class="btn btn-outline-secondary" type="button">Button</button>
<button class="btn btn-outline-secondary" type="button">Button</button>
</div>带下拉列表的按钮
<div class="input-group mb-3">
<button class="btn btn-outline-secondary dropdown-toggle" type="button" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>
<ul class="dropdown-menu">
<li><a class="dropdown-item" href="#">Action</a></li>
<li><a class="dropdown-item" href="#">Another action</a></li>
<li><a class="dropdown-item" href="#">Something else here</a></li>
<li><hr class="dropdown-divider"></li>
<li><a class="dropdown-item" href="#">Separated link</a></li>
</ul>
<input type="text" class="form-control" aria-label="Text input with dropdown button">
</div>
<div class="input-group mb-3">
<input type="text" class="form-control" aria-label="Text input with dropdown button">
<button class="btn btn-outline-secondary dropdown-toggle" type="button" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>
<ul class="dropdown-menu dropdown-menu-end">
<li><a class="dropdown-item" href="#">Action</a></li>
<li><a class="dropdown-item" href="#">Another action</a></li>
<li><a class="dropdown-item" href="#">Something else here</a></li>
<li><hr class="dropdown-divider"></li>
<li><a class="dropdown-item" href="#">Separated link</a></li>
</ul>
</div>
<div class="input-group">
<button class="btn btn-outline-secondary dropdown-toggle" type="button" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>
<ul class="dropdown-menu">
<li><a class="dropdown-item" href="#">Action before</a></li>
<li><a class="dropdown-item" href="#">Another action before</a></li>
<li><a class="dropdown-item" href="#">Something else here</a></li>
<li><hr class="dropdown-divider"></li>
<li><a class="dropdown-item" href="#">Separated link</a></li>
</ul>
<input type="text" class="form-control" aria-label="Text input with 2 dropdown buttons">
<button class="btn btn-outline-secondary dropdown-toggle" type="button" data-bs-toggle="dropdown" aria-expanded="false">Dropdown</button>
<ul class="dropdown-menu dropdown-menu-end">
<li><a class="dropdown-item" href="#">Action</a></li>
<li><a class="dropdown-item" href="#">Another action</a></li>
<li><a class="dropdown-item" href="#">Something else here</a></li>
<li><hr class="dropdown-divider"></li>
<li><a class="dropdown-item" href="#">Separated link</a></li>
</ul>
</div>分段按钮
<div class="input-group mb-3">
<button type="button" class="btn btn-outline-secondary">Action</button>
<button type="button" class="btn btn-outline-secondary dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
<span class="visually-hidden">Toggle Dropdown</span>
</button>
<ul class="dropdown-menu">
<li><a class="dropdown-item" href="#">Action</a></li>
<li><a class="dropdown-item" href="#">Another action</a></li>
<li><a class="dropdown-item" href="#">Something else here</a></li>
<li><hr class="dropdown-divider"></li>
<li><a class="dropdown-item" href="#">Separated link</a></li>
</ul>
<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">
<button type="button" class="btn btn-outline-secondary">Action</button>
<button type="button" class="btn btn-outline-secondary dropdown-toggle dropdown-toggle-split" data-bs-toggle="dropdown" aria-expanded="false">
<span class="visually-hidden">Toggle Dropdown</span>
</button>
<ul class="dropdown-menu dropdown-menu-end">
<li><a class="dropdown-item" href="#">Action</a></li>
<li><a class="dropdown-item" href="#">Another action</a></li>
<li><a class="dropdown-item" href="#">Something else here</a></li>
<li><hr class="dropdown-divider"></li>
<li><a class="dropdown-item" href="#">Separated link</a></li>
</ul>
</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 select
<div class="input-group mb-3">
<label class="input-group-text" for="inputGroupSelect01">Options</label>
<select class="form-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="form-select" id="inputGroupSelect02">
<option selected>Choose...</option>
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
</select>
<label class="input-group-text" for="inputGroupSelect02">Options</label>
</div>
<div class="input-group mb-3">
<button class="btn btn-outline-secondary" type="button">Button</button>
<select class="form-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="form-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>
<button class="btn btn-outline-secondary" type="button">Button</button>
</div>自定义 file input
<div class="input-group mb-3">
<label class="input-group-text" for="inputGroupFile01">Upload</label>
<input type="file" class="form-control" id="inputGroupFile01">
</div>
<div class="input-group mb-3">
<input type="file" class="form-control" id="inputGroupFile02">
<label class="input-group-text" for="inputGroupFile02">Upload</label>
</div>
<div class="input-group mb-3">
<button class="btn btn-outline-secondary" type="button" id="inputGroupFileAddon03">Button</button>
<input type="file" class="form-control" id="inputGroupFile03" aria-describedby="inputGroupFileAddon03" aria-label="Upload">
</div>
<div class="input-group">
<input type="file" class="form-control" id="inputGroupFile04" aria-describedby="inputGroupFileAddon04" aria-label="Upload">
<button class="btn btn-outline-secondary" type="button" id="inputGroupFileAddon04">Button</button>
</div>