浮动标签
创建漂浮在您的输入字段上的精美简单的表单标签。
例子
将一对<input class="form-control">
and<label>
元素包裹起来,.form-floating
以使用 Bootstrap 的文本表单字段启用浮动标签。placeholder
每个都需要 A,因为<input>
我们的纯 CSS 浮动标签方法使用:placeholder-shown
伪元素。另请注意,<input>
必须先出现,以便我们可以使用兄弟选择器(例如,~
)。
<div class="form-floating mb-3">
<input type="email" class="form-control" id="floatingInput" placeholder="name@example.com">
<label for="floatingInput">Email address</label>
</div>
<div class="form-floating">
<input type="password" class="form-control" id="floatingPassword" placeholder="Password">
<label for="floatingPassword">Password</label>
</div>
当有一个value
已经定义的时候,<label>
s 会自动调整到它们的浮动位置。
<form class="form-floating">
<input type="email" class="form-control" id="floatingInputValue" placeholder="name@example.com" value="test@example.com">
<label for="floatingInputValue">Input with value</label>
</form>
表单验证样式也按预期工作。
<form class="form-floating">
<input type="email" class="form-control is-invalid" id="floatingInputInvalid" placeholder="name@example.com" value="test@example.com">
<label for="floatingInputInvalid">Invalid input</label>
</form>
文本区域
默认情况下,<textarea>
s 与 s.form-control
的高度相同<input>
。
<div class="form-floating">
<textarea class="form-control" placeholder="Leave a comment here" id="floatingTextarea"></textarea>
<label for="floatingTextarea">Comments</label>
</div>
要在您的 上设置自定义高度<textarea>
,请不要使用该rows
属性。相反,设置显式height
(内联或通过自定义 CSS)。
<div class="form-floating">
<textarea class="form-control" placeholder="Leave a comment here" id="floatingTextarea2" style="height: 100px"></textarea>
<label for="floatingTextarea2">Comments</label>
</div>
选择
除了.form-control
,浮动标签仅在.form-select
s 上可用。它们的工作方式相同,但与<input>
s 不同的是,它们将始终<label>
以浮动状态显示。选择 withsize
和multiple
不受支持。
<div class="form-floating">
<select class="form-select" id="floatingSelect" aria-label="Floating label select example">
<option selected>Open this select menu</option>
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
</select>
<label for="floatingSelect">Works with selects</label>
</div>
残疾人
在输入、文本区域或选择上添加disabled
布尔属性,使其呈现灰色外观、删除指针事件并防止聚焦。
<div class="form-floating mb-3">
<input type="email" class="form-control" id="floatingInputDisabled" placeholder="name@example.com" disabled>
<label for="floatingInputDisabled">Email address</label>
</div>
<div class="form-floating mb-3">
<textarea class="form-control" placeholder="Leave a comment here" id="floatingTextareaDisabled" disabled></textarea>
<label for="floatingTextareaDisabled">Comments</label>
</div>
<div class="form-floating mb-3">
<textarea class="form-control" placeholder="Leave a comment here" id="floatingTextarea2Disabled" style="height: 100px" disabled></textarea>
<label for="floatingTextarea2Disabled">Comments</label>
</div>
<div class="form-floating">
<select class="form-select" id="floatingSelectDisabled" aria-label="Floating label disabled select example" disabled>
<option selected>Open this select menu</option>
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
</select>
<label for="floatingSelectDisabled">Works with selects</label>
</div>
只读明文
浮动标签还支持.form-control-plaintext
,这有助于在<input>
不影响页面布局的情况下从可编辑值切换为纯文本值。
<div class="form-floating mb-3">
<input type="email" readonly class="form-control-plaintext" id="floatingEmptyPlaintextInput" placeholder="name@example.com">
<label for="floatingEmptyPlaintextInput">Empty input</label>
</div>
<div class="form-floating mb-3">
<input type="email" readonly class="form-control-plaintext" id="floatingPlaintextInput" placeholder="name@example.com" value="name@example.com">
<label for="floatingPlaintextInput">Input with value</label>
</div>
输入组
浮动标签也支持.input-group
.
<div class="input-group mb-3">
<span class="input-group-text">@</span>
<div class="form-floating">
<input type="text" class="form-control" id="floatingInputGroup1" placeholder="Username">
<label for="floatingInputGroup1">Username</label>
</div>
</div>
当.input-group
与.form-floating
表单验证一起使用时,-feedback
应将 放在 之外.form-floating
,但放在.input-group
. 这意味着需要使用 javascript 显示反馈。
<div class="input-group has-validation">
<span class="input-group-text">@</span>
<div class="form-floating is-invalid">
<input type="text" class="form-control is-invalid" id="floatingInputGroup2" placeholder="Username" required>
<label for="floatingInputGroup2">Username</label>
</div>
<div class="invalid-feedback">
Please choose a username.
</div>
</div>
布局
使用 Bootstrap 网格系统时,请确保将表单元素放置在列类中。
<div class="row g-2">
<div class="col-md">
<div class="form-floating">
<input type="email" class="form-control" id="floatingInputGrid" placeholder="name@example.com" value="mdo@example.com">
<label for="floatingInputGrid">Email address</label>
</div>
</div>
<div class="col-md">
<div class="form-floating">
<select class="form-select" id="floatingSelectGrid">
<option selected>Open this select menu</option>
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
</select>
<label for="floatingSelectGrid">Works with selects</label>
</div>
</div>
</div>
SASS
变量
$form-floating-height: add(3.5rem, $input-height-border);
$form-floating-line-height: 1.25;
$form-floating-padding-x: $input-padding-x;
$form-floating-padding-y: 1rem;
$form-floating-input-padding-t: 1.625rem;
$form-floating-input-padding-b: .625rem;
$form-floating-label-height: 1.875em;
$form-floating-label-opacity: .65;
$form-floating-label-transform: scale(.85) translateY(-.5rem) translateX(.15rem);
$form-floating-label-disabled-color: $gray-600;
$form-floating-transition: opacity .1s ease-in-out, transform .1s ease-in-out;