Bootstrap V5.3 : Validation 表单验证中文翻译版

通过浏览器默认行为或自定义样式和 JavaScript，通过 HTML5 表单验证向用户提供有价值、可作的反馈。

我们知道，目前无法访问客户端自定义验证样式和工具提示，因为它们没有暴露于辅助技术。在我们开发解决方案时，我们建议使用服务器端选项或默认浏览器验证方法。

运作方式

以下是表单验证与 Bootstrap 的工作原理：

HTML 表单验证通过 CSS 的两个伪类和 .它适用于、和元素。:invalid:valid<input><select><textarea>
Bootstrap 将和样式的范围限定为父类，通常应用于 .否则，任何没有值的必填字段在页面加载时都会显示为无效。这样，您可以选择何时激活它们（通常是在尝试提交表单之后）。:invalid:valid.was-validated<form>
要重置表单的外观（例如，在使用 Ajax 的动态表单提交的情况下），请在提交后再次从中删除该类。.was-validated<form>
作为后备，可以使用类代替伪类进行服务器端验证。它们不需要父类。.is-invalid.is-valid.was-validated
由于 CSS 工作方式的限制，如果没有自定义 JavaScript 的帮助，我们（目前）无法将样式应用于 DOM 中表单控件之前的样式。<label>
所有现代浏览器都支持约束验证 API，这是一系列用于验证表单控件的 JavaScript 方法。
反馈消息可能会使用浏览器默认设置（每个浏览器都不同，并且无法通过 CSS 设置样式）或带有附加 HTML 和 CSS 的自定义反馈样式。
您可以使用 JavaScript 提供自定义有效性消息。setCustomValidity

考虑到这一点，请考虑以下演示，了解我们的自定义表单验证样式、可选的服务器端类和浏览器默认值。

自定义样式

对于自定义 Bootstrap 表单验证消息，您需要将布尔属性添加到 .这会禁用浏览器默认反馈工具提示，但仍提供对 JavaScript 中表单验证 API 的访问。尝试提交下面的表格;我们的 JavaScript 将拦截提交按钮并将反馈转发给您。尝试提交时，你将看到应用于表单控件的和样式。novalidate<form>:invalid:valid

自定义反馈样式应用自定义颜色、边框、焦点样式和背景图标，以更好地传达反馈。s 的背景图标仅与一起使用，而不能与一起使用。<select>.form-select.form-control

[HTML全文]

<form class="row g-3 needs-validation" novalidate>
  <div class="col-md-4">
    <label for="validationCustom01" class="form-label">First name</label>
    <input type="text" class="form-control" id="validationCustom01" value="Mark" required>
    <div class="valid-feedback">
      Looks good!
    </div>
  </div>
  <div class="col-md-4">
    <label for="validationCustom02" class="form-label">Last name</label>
    <input type="text" class="form-control" id="validationCustom02" value="Otto" required>
    <div class="valid-feedback">
      Looks good!
    </div>
  </div>
  <div class="col-md-4">
    <label for="validationCustomUsername" class="form-label">Username</label>
    <div class="input-group has-validation">
      <span class="input-group-text" id="inputGroupPrepend">@</span>
      <input type="text" class="form-control" id="validationCustomUsername" aria-describedby="inputGroupPrepend" required>
      <div class="invalid-feedback">
        Please choose a username.
      </div>
    </div>
  </div>
  <div class="col-md-6">
    <label for="validationCustom03" class="form-label">City</label>
    <input type="text" class="form-control" id="validationCustom03" required>
    <div class="invalid-feedback">
      Please provide a valid city.
    </div>
  </div>
  <div class="col-md-3">
    <label for="validationCustom04" class="form-label">State</label>
    <select class="form-select" id="validationCustom04" required>
      <option selected disabled value="">Choose...</option>
      <option>...</option>
    </select>
    <div class="invalid-feedback">
      Please select a valid state.
    </div>
  </div>
  <div class="col-md-3">
    <label for="validationCustom05" class="form-label">Zip</label>
    <input type="text" class="form-control" id="validationCustom05" required>
    <div class="invalid-feedback">
      Please provide a valid zip.
    </div>
  </div>
  <div class="col-12">
    <div class="form-check">
      <input class="form-check-input" type="checkbox" value="" id="invalidCheck" required>
      <label class="form-check-label" for="invalidCheck">
        Agree to terms and conditions
      </label>
      <div class="invalid-feedback">
        You must agree before submitting.
      </div>
    </div>
  </div>
  <div class="col-12">
    <button class="btn btn-primary" type="submit">Submit form</button>
  </div>
</form>

// Example starter JavaScript for disabling form submissions if there are invalid fields
(() => {
  'use strict'

  // Fetch all the forms we want to apply custom Bootstrap validation styles to
  const forms = document.querySelectorAll('.needs-validation')

  // Loop over them and prevent submission
  Array.from(forms).forEach(form => {
    form.addEventListener('submit', event => {
      if (!form.checkValidity()) {
        event.preventDefault()
        event.stopPropagation()
      }

      form.classList.add('was-validated')
    }, false)
  })
})()

浏览器默认值

对自定义验证反馈消息或编写 JavaScript 来更改表单行为不感兴趣？一切都很好，您可以使用浏览器默认值。请尝试提交下面的表格。根据您的浏览器和作系统，您会看到略有不同的反馈风格。

虽然这些反馈样式无法使用 CSS 设置样式，但您仍然可以通过 JavaScript 自定义反馈文本。

[HTML全文]

<form class="row g-3">
  <div class="col-md-4">
    <label for="validationDefault01" class="form-label">First name</label>
    <input type="text" class="form-control" id="validationDefault01" value="Mark" required>
  </div>
  <div class="col-md-4">
    <label for="validationDefault02" class="form-label">Last name</label>
    <input type="text" class="form-control" id="validationDefault02" value="Otto" required>
  </div>
  <div class="col-md-4">
    <label for="validationDefaultUsername" class="form-label">Username</label>
    <div class="input-group">
      <span class="input-group-text" id="inputGroupPrepend2">@</span>
      <input type="text" class="form-control" id="validationDefaultUsername" aria-describedby="inputGroupPrepend2" required>
    </div>
  </div>
  <div class="col-md-6">
    <label for="validationDefault03" class="form-label">City</label>
    <input type="text" class="form-control" id="validationDefault03" required>
  </div>
  <div class="col-md-3">
    <label for="validationDefault04" class="form-label">State</label>
    <select class="form-select" id="validationDefault04" required>
      <option selected disabled value="">Choose...</option>
      <option>...</option>
    </select>
  </div>
  <div class="col-md-3">
    <label for="validationDefault05" class="form-label">Zip</label>
    <input type="text" class="form-control" id="validationDefault05" required>
  </div>
  <div class="col-12">
    <div class="form-check">
      <input class="form-check-input" type="checkbox" value="" id="invalidCheck2" required>
      <label class="form-check-label" for="invalidCheck2">
        Agree to terms and conditions
      </label>
    </div>
  </div>
  <div class="col-12">
    <button class="btn btn-primary" type="submit">Submit form</button>
  </div>
</form>

服务器端

我们建议使用客户端验证，但如果您需要服务器端验证，您可以使用和指示无效和有效的表单字段。请注意，这些类也支持。.is-invalid.is-valid.invalid-feedback

对于无效字段，请确保无效反馈/错误消息与相关表单字段相关联（请注意，如果该字段已指向其他表单文本，则此属性允许引用多个表单文本）。aria-describedbyid

要解决边界半径问题，输入组需要一个额外的类。.has-validation

[HTML全文]

<form class="row g-3">
  <div class="col-md-4">
    <label for="validationServer01" class="form-label">First name</label>
    <input type="text" class="form-control is-valid" id="validationServer01" value="Mark" required>
    <div class="valid-feedback">
      Looks good!
    </div>
  </div>
  <div class="col-md-4">
    <label for="validationServer02" class="form-label">Last name</label>
    <input type="text" class="form-control is-valid" id="validationServer02" value="Otto" required>
    <div class="valid-feedback">
      Looks good!
    </div>
  </div>
  <div class="col-md-4">
    <label for="validationServerUsername" class="form-label">Username</label>
    <div class="input-group has-validation">
      <span class="input-group-text" id="inputGroupPrepend3">@</span>
      <input type="text" class="form-control is-invalid" id="validationServerUsername" aria-describedby="inputGroupPrepend3 validationServerUsernameFeedback" required>
      <div id="validationServerUsernameFeedback" class="invalid-feedback">
        Please choose a username.
      </div>
    </div>
  </div>
  <div class="col-md-6">
    <label for="validationServer03" class="form-label">City</label>
    <input type="text" class="form-control is-invalid" id="validationServer03" aria-describedby="validationServer03Feedback" required>
    <div id="validationServer03Feedback" class="invalid-feedback">
      Please provide a valid city.
    </div>
  </div>
  <div class="col-md-3">
    <label for="validationServer04" class="form-label">State</label>
    <select class="form-select is-invalid" id="validationServer04" aria-describedby="validationServer04Feedback" required>
      <option selected disabled value="">Choose...</option>
      <option>...</option>
    </select>
    <div id="validationServer04Feedback" class="invalid-feedback">
      Please select a valid state.
    </div>
  </div>
  <div class="col-md-3">
    <label for="validationServer05" class="form-label">Zip</label>
    <input type="text" class="form-control is-invalid" id="validationServer05" aria-describedby="validationServer05Feedback" required>
    <div id="validationServer05Feedback" class="invalid-feedback">
      Please provide a valid zip.
    </div>
  </div>
  <div class="col-12">
    <div class="form-check">
      <input class="form-check-input is-invalid" type="checkbox" value="" id="invalidCheck3" aria-describedby="invalidCheck3Feedback" required>
      <label class="form-check-label" for="invalidCheck3">
        Agree to terms and conditions
      </label>
      <div id="invalidCheck3Feedback" class="invalid-feedback">
        You must agree before submitting.
      </div>
    </div>
  </div>
  <div class="col-12">
    <button class="btn btn-primary" type="submit">Submit form</button>
  </div>
</form>

支持的元素

验证样式可用于以下表单控件和组件：

<input>s 和 s（包括输入组中最多一个）<textarea>.form-control.form-control
<select>s 替换为.form-select
.form-checks

[HTML全文]

<form class="was-validated">
  <div class="mb-3">
    <label for="validationTextarea" class="form-label">Textarea</label>
    <textarea class="form-control" id="validationTextarea" placeholder="Required example textarea" required></textarea>
    <div class="invalid-feedback">
      Please enter a message in the textarea.
    </div>
  </div>

  <div class="form-check mb-3">
    <input type="checkbox" class="form-check-input" id="validationFormCheck1" required>
    <label class="form-check-label" for="validationFormCheck1">Check this checkbox</label>
    <div class="invalid-feedback">Example invalid feedback text</div>
  </div>

  <div class="form-check">
    <input type="radio" class="form-check-input" id="validationFormCheck2" name="radio-stacked" required>
    <label class="form-check-label" for="validationFormCheck2">Toggle this radio</label>
  </div>
  <div class="form-check mb-3">
    <input type="radio" class="form-check-input" id="validationFormCheck3" name="radio-stacked" required>
    <label class="form-check-label" for="validationFormCheck3">Or toggle this other radio</label>
    <div class="invalid-feedback">More example invalid feedback text</div>
  </div>

  <div class="mb-3">
    <select class="form-select" required aria-label="select example">
      <option value="">Open this select menu</option>
      <option value="1">One</option>
      <option value="2">Two</option>
      <option value="3">Three</option>
    </select>
    <div class="invalid-feedback">Example invalid select feedback</div>
  </div>

  <div class="mb-3">
    <input type="file" class="form-control" aria-label="file example" required>
    <div class="invalid-feedback">Example invalid form file feedback</div>
  </div>

  <div class="mb-3">
    <button class="btn btn-primary" type="submit" disabled>Submit form</button>
  </div>
</form>

工具提示

如果表单布局允许，则可以将类交换为类，以在样式化工具提示中显示验证反馈。确保有一个父级，用于工具提示定位。在下面的示例中，我们的列类已经具有此功能，但您的项目可能需要替代设置。.{valid|invalid}-feedback.{valid|invalid}-tooltipposition: relative

[HTML全文]

<form class="row g-3 needs-validation" novalidate>
  <div class="col-md-4 position-relative">
    <label for="validationTooltip01" class="form-label">First name</label>
    <input type="text" class="form-control" id="validationTooltip01" value="Mark" required>
    <div class="valid-tooltip">
      Looks good!
    </div>
  </div>
  <div class="col-md-4 position-relative">
    <label for="validationTooltip02" class="form-label">Last name</label>
    <input type="text" class="form-control" id="validationTooltip02" value="Otto" required>
    <div class="valid-tooltip">
      Looks good!
    </div>
  </div>
  <div class="col-md-4 position-relative">
    <label for="validationTooltipUsername" class="form-label">Username</label>
    <div class="input-group has-validation">
      <span class="input-group-text" id="validationTooltipUsernamePrepend">@</span>
      <input type="text" class="form-control" id="validationTooltipUsername" aria-describedby="validationTooltipUsernamePrepend" required>
      <div class="invalid-tooltip">
        Please choose a unique and valid username.
      </div>
    </div>
  </div>
  <div class="col-md-6 position-relative">
    <label for="validationTooltip03" class="form-label">City</label>
    <input type="text" class="form-control" id="validationTooltip03" required>
    <div class="invalid-tooltip">
      Please provide a valid city.
    </div>
  </div>
  <div class="col-md-3 position-relative">
    <label for="validationTooltip04" class="form-label">State</label>
    <select class="form-select" id="validationTooltip04" required>
      <option selected disabled value="">Choose...</option>
      <option>...</option>
    </select>
    <div class="invalid-tooltip">
      Please select a valid state.
    </div>
  </div>
  <div class="col-md-3 position-relative">
    <label for="validationTooltip05" class="form-label">Zip</label>
    <input type="text" class="form-control" id="validationTooltip05" required>
    <div class="invalid-tooltip">
      Please provide a valid zip.
    </div>
  </div>
  <div class="col-12">
    <button class="btn btn-primary" type="submit">Submit form</button>
  </div>
</form>

CSS系统

变量

在 v5.3.0 中添加

作为 Bootstrap 不断发展的 CSS 变量方法的一部分，表单现在使用本地 CSS 变量进行验证，以增强实时自定义。CSS 变量的值是通过 Sass 设置的，因此仍然支持 Sass 自定义。

scss/_root.scss

--#{$prefix}form-valid-color: #{$form-valid-color};
--#{$prefix}form-valid-border-color: #{$form-valid-border-color};
--#{$prefix}form-invalid-color: #{$form-invalid-color};
--#{$prefix}form-invalid-border-color: #{$form-invalid-border-color};

这些变量也是颜色模式自适应的，这意味着它们在深色模式下会改变颜色。

Sass 变量

scss/_variables.scss

$form-feedback-margin-top:          $form-text-margin-top;
$form-feedback-font-size:           $form-text-font-size;
$form-feedback-font-style:          $form-text-font-style;
$form-feedback-valid-color:         $success;
$form-feedback-invalid-color:       $danger;

$form-feedback-icon-valid-color:    $form-feedback-valid-color;
$form-feedback-icon-valid:          url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 8 8'><path fill='#{$form-feedback-icon-valid-color}' d='M2.3 6.73.6 4.53c-.4-1.04.46-1.4 1.1-.8l1.1 1.4 3.4-3.8c.6-.63 1.6-.27 1.2.7l-4 4.6c-.43.5-.8.4-1.1.1'/></svg>");
$form-feedback-icon-invalid-color:  $form-feedback-invalid-color;
$form-feedback-icon-invalid:        url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 12 12' width='12' height='12' fill='none' stroke='#{$form-feedback-icon-invalid-color}'><circle cx='6' cy='6' r='4.5'/><path stroke-linejoin='round' d='M5.8 3.6h.4L6 6.5z'/><circle cx='6' cy='8.2' r='.6' fill='#{$form-feedback-icon-invalid-color}' stroke='none'/></svg>");

scss/_variables.scss

$form-valid-color:                  $form-feedback-valid-color;
$form-valid-border-color:           $form-feedback-valid-color;
$form-invalid-color:                $form-feedback-invalid-color;
$form-invalid-border-color:         $form-feedback-invalid-color;

scss/_variables-dark.scss

$form-valid-color-dark:             $green-300;
$form-valid-border-color-dark:      $green-300;
$form-invalid-color-dark:           $red-300;
$form-invalid-border-color-dark:    $red-300;

Sass 混合

通过我们的循环，将两个 mixin 组合在一起，以生成我们的表单验证反馈样式。

scss/mixins/_forms.scss

@mixin form-validation-state-selector($state) {
  @if ($state == "valid" or $state == "invalid") {
    .was-validated #{if(&, "&", "")}:#{$state},
    #{if(&, "&", "")}.is-#{$state} {
      @content;
    }
  } @else {
    #{if(&, "&", "")}.is-#{$state} {
      @content;
    }
  }
}

@mixin form-validation-state(
  $state,
  $color,
  $icon,
  $tooltip-color: color-contrast($color),
  $tooltip-bg-color: rgba($color, $form-feedback-tooltip-opacity),
  $focus-box-shadow: 0 0 $input-btn-focus-blur $input-focus-width rgba($color, $input-btn-focus-color-opacity),
  $border-color: $color
) {
  .#{$state}-feedback {
    display: none;
    width: 100%;
    margin-top: $form-feedback-margin-top;
    @include font-size($form-feedback-font-size);
    font-style: $form-feedback-font-style;
    color: $color;
  }

  .#{$state}-tooltip {
    position: absolute;
    top: 100%;
    z-index: 5;
    display: none;
    max-width: 100%; // Contain to parent when possible
    padding: $form-feedback-tooltip-padding-y $form-feedback-tooltip-padding-x;
    margin-top: .1rem;
    @include font-size($form-feedback-tooltip-font-size);
    line-height: $form-feedback-tooltip-line-height;
    color: $tooltip-color;
    background-color: $tooltip-bg-color;
    @include border-radius($form-feedback-tooltip-border-radius);
  }

  @include form-validation-state-selector($state) {
    ~ .#{$state}-feedback,
    ~ .#{$state}-tooltip {
      display: block;
    }
  }

  .form-control {
    @include form-validation-state-selector($state) {
      border-color: $border-color;

      @if $enable-validation-icons {
        padding-right: $input-height-inner;
        background-image: escape-svg($icon);
        background-repeat: no-repeat;
        background-position: right $input-height-inner-quarter center;
        background-size: $input-height-inner-half $input-height-inner-half;
      }

      &:focus {
        border-color: $border-color;
        @if $enable-shadows {
          @include box-shadow($input-box-shadow, $focus-box-shadow);
        } @else {
          // Avoid using mixin so we can pass custom focus shadow properly
          box-shadow: $focus-box-shadow;
        }
      }
    }
  }

  // stylelint-disable-next-line selector-no-qualifying-type
  textarea.form-control {
    @include form-validation-state-selector($state) {
      @if $enable-validation-icons {
        padding-right: $input-height-inner;
        background-position: top $input-height-inner-quarter right $input-height-inner-quarter;
      }
    }
  }

  .form-select {
    @include form-validation-state-selector($state) {
      border-color: $border-color;

      @if $enable-validation-icons {
        &:not([multiple]):not([size]),
        &:not([multiple])[size="1"] {
          --#{$prefix}form-select-bg-icon: #{escape-svg($icon)};
          padding-right: $form-select-feedback-icon-padding-end;
          background-position: $form-select-bg-position, $form-select-feedback-icon-position;
          background-size: $form-select-bg-size, $form-select-feedback-icon-size;
        }
      }

      &:focus {
        border-color: $border-color;
        @if $enable-shadows {
          @include box-shadow($form-select-box-shadow, $focus-box-shadow);
        } @else {
          // Avoid using mixin so we can pass custom focus shadow properly
          box-shadow: $focus-box-shadow;
        }
      }
    }
  }

  .form-control-color {
    @include form-validation-state-selector($state) {
      @if $enable-validation-icons {
        width: add($form-color-width, $input-height-inner);
      }
    }
  }

  .form-check-input {
    @include form-validation-state-selector($state) {
      border-color: $border-color;

      &:checked {
        background-color: $color;
      }

      &:focus {
        box-shadow: $focus-box-shadow;
      }

      ~ .form-check-label {
        color: $color;
      }
    }
  }
  .form-check-inline .form-check-input {
    ~ .#{$state}-feedback {
      margin-left: .5em;
    }
  }

  .input-group {
    > .form-control:not(:focus),
    > .form-select:not(:focus),
    > .form-floating:not(:focus-within) {
      @include form-validation-state-selector($state) {
        @if $state == "valid" {
          z-index: 3;
        } @else if $state == "invalid" {
          z-index: 4;
        }
      }
    }
  }
}

萨斯地图

这是来自的验证 Sass 映射。覆盖或扩展此状态以生成不同的或其他状态。_variables.scss

scss/_variables.scss

$form-validation-states: (
  "valid": (
    "color": var(--#{$prefix}form-valid-color),
    "icon": $form-feedback-icon-valid,
    "tooltip-color": #fff,
    "tooltip-bg-color": var(--#{$prefix}success),
    "focus-box-shadow": 0 0 $input-btn-focus-blur $input-focus-width rgba(var(--#{$prefix}success-rgb), $input-btn-focus-color-opacity),
    "border-color": var(--#{$prefix}form-valid-border-color),
  ),
  "invalid": (
    "color": var(--#{$prefix}form-invalid-color),
    "icon": $form-feedback-icon-invalid,
    "tooltip-color": #fff,
    "tooltip-bg-color": var(--#{$prefix}danger),
    "focus-box-shadow": 0 0 $input-btn-focus-blur $input-focus-width rgba(var(--#{$prefix}danger-rgb), $input-btn-focus-color-opacity),
    "border-color": var(--#{$prefix}form-invalid-border-color),
  )
);

地图可以包含三个可选参数，以覆盖工具提示和焦点样式。$form-validation-states

Sass 循环

用于迭代映射值以生成验证样式。对上述 Sass 映射的任何修改都将通过此循环反映在编译的 CSS 中。$form-validation-states

scss/forms/_validation.scss

@each $state, $data in $form-validation-states {
  @include form-validation-state($state, $data...);
}

定制

验证状态可以通过 Sass 与映射进行自定义。位于我们的文件中，此 Sass 映射是我们生成默认/验证状态的方式。包括一个嵌套地图，用于自定义每个州的颜色、图标、工具提示颜色和焦点阴影。虽然浏览器不支持其他状态，但使用自定义样式的浏览器可以轻松添加更复杂的表单反馈。$form-validation-states_variables.scssvalidinvalid

Bootstrap V5.3 中文手册

入门指南 Getting started

定制化 Customize

布局方式 Layout

内容样式 Content

表单控件 Forms

组件集合 Components

辅助工具 Helpers

工具类库 Utilities

功能扩展 Extend

关于Bootstrap

Validation 表单验证

运作方式

自定义样式

浏览器默认值

服务器端

支持的元素

工具提示

CSS系统

变量

Sass 变量

Sass 混合

萨斯地图

Sass 循环

定制