form.md 13 KB
title: Form
lang: en-US
Form
Form consists of input, radio, select, checkbox and so on. With form, you can collect, verify and submit data.
:::tip
The component has been upgraded with a flex layout to replace the old float layout.
:::
Basic Form
It includes all kinds of input items, such as input, select, radio and checkbox.
:::demo In each form component, you need a form-item field to be the container of your input item.
form/basic-form
:::
:::tip
W3C regulates that
When there is only one single-line text input field in a form, the user agent should accept Enter in that field as a request to submit the form.
To prevent this behavior, you can add @submit.prevent on <el-form>.
:::
Inline Form
When the vertical space is limited and the form is relatively simple, you can put it in one line.
:::demo Set the inline attribute to true and the form will be inline.
form/inline-form
:::
Alignment
Depending on your design, there are several different ways to align your label element.
:::demo The label-position attribute decides how labels align, it can be top or left. When set to top, labels will be placed at the top of the form field.
form/alignment
:::
Validation
Form component allows you to verify your data, helping you find and correct errors.
:::demo Just add the rules attribute for Form component, pass validation rules, and set prop attribute for FormItem as a specific key that needs to be validated. See more information at async-validator.
form/validation
:::
Custom Validation Rules
This example shows how to customize your own validation rules to finish a two-factor password verification.
:::demo Here we use status-icon to reflect validation result as an icon.
form/custom-validation
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:::tip
Custom validate callback function must be called. See more advanced usage at async-validator.
:::
Add/Delete Form Item
:::demo In addition to passing all validation rules at once on the form component, you can also pass the validation rules or delete rules on a single form field dynamically.
form/form-items
:::
Number Validate
:::demo Number Validate need a .number modifier added on the input v-model binding，it's used to transform the string value to the number which is provided by Vue.
form/number-validate
:::
:::tip
When an el-form-item is nested in another el-form-item, its label width will be 0. You can set label-width on that el-form-item if needed.
:::
Size Control
All components in a Form inherit their size attribute from that Form. Similarly, FormItem also has a size attribute.
:::demo Still you can fine tune each component's size if you don't want that component to inherit its size from From or FormItem.
form/size-control
:::
Accessibility
When only a single input (or related control such as select or checkbox) is inside of a el-form-item, the form item's label will automatically be attached to that input. However, if multiple inputs are inside of the el-form-item, the form item will be assigned the WAI-ARIA role of group instead. In this case, it is your responsibility to assign assistive labels to the individual inputs.
:::demo
form/accessibility
:::
Form API
Form Attributes
| Name | Description | Type | Default |
|---|---|---|---|
model |
Data of form component. | Record<string, any> |
— |
rules |
Validation rules of form. | FormRules |
— |
inline |
Whether the form is inline. | boolean |
false |
label-position |
Position of label. If set to 'left' or 'right', label-width prop is also required. |
'left' \| 'right' \| 'top' |
'right' |
label-width |
Width of label, e.g. '50px'. All its direct child form items will inherit this value. auto is supported. |
string \| number |
— |
label-suffix |
Suffix of the label. | string |
— |
hide-required-asterisk |
Whether to hide required fields should have a red asterisk (star) beside their labels. | boolean |
false |
require-asterisk-position |
Position of asterisk. | 'left' \| 'right' |
'left' |
show-message |
Whether to show the error message. | boolean |
true |
inline-message |
Whether to display the error message inline with the form item. | boolean |
false |
status-icon |
Whether to display an icon indicating the validation result. | boolean |
false |
validate-on-rule-change |
Whether to trigger validation when the rules prop is changed. |
boolean |
true |
size |
Control the size of components in this form. | 'large' \| 'default' \| 'small' |
— |
disabled |
Whether to disable all components in this form. If set to true, it will override the disabled prop of the inner component. |
boolean |
false |
scroll-to-error |
When validation fails, scroll to the first error form entry. | boolean |
false |
Form Methods
| Method | Description | Type |
|---|---|---|
validate |
Validate the whole form. Receives a callback or returns Promise. |
(callback?: (isValid: boolean, invalidFields?: ValidateFieldsError) => void) => Promise<void> |
validateField |
Validate specified fields. | (props?: Arrayable<FormItemProp>, callback?: (isValid: boolean, invalidFields?: ValidateFieldsError) => void) => Promise<void> |
resetFields |
Reset specified fields and remove validation result. | (props?: Arrayable<FormItemProp>) => void |
scrollToField |
Scroll to the specified fields. | (prop: FormItemProp) => void |
clearValidate |
Clear validation message for specified fields. | (props?: Arrayable<FormItemProp>) => void |
Form Events
| Name | Description | Parameters |
|---|---|---|
validate |
triggers after a form item is validated | (prop: FormItemProp, isValid: boolean, message: string) => void |
Form Slots
| Name | Description | Subtags |
|---|---|---|
| - | customize default content | FormItem |
Form Item API
Form Item Attributes
| Name | Description | Type | Default |
|---|---|---|---|
prop |
A key of model. It could be an array of property paths (e.g ['a', 'b', 0]). In the use of validate and resetFields method, the attribute is required. |
string \| string[] |
— |
label |
Label text. | string |
— |
label-width |
Width of label, e.g. '50px'. 'auto' is supported. |
string \| number |
— |
required |
Whether the field is required or not, will be determined by validation rules if omitted. | boolean |
false |
rules |
Validation rules of form, see the following table, more advanced usage at async-validator. | FormItemRule \| FormItemRule[] |
— |
error |
Field error message, set its value and the field will validate error and show this message immediately. | string |
— |
show-message |
Whether to show the error message. | boolean |
true |
inline-message |
Inline style validate message. | boolean |
false |
size |
Control the size of components in this form-item. | 'large' \| 'default' \| 'small' |
'default' |
FormItemRule
| Name | Description | Type | Default |
|---|---|---|---|
trigger |
How the validator is triggered. | 'blur' \| 'change' |
— |
Form Item Slots
| Name | Description | Slot Scope |
|---|---|---|
| — | Content of Form Item. | — |
label |
Custom content to display on label. | { label } |
error |
Custom content to display validation message. | { error } |
Form Item Methods
| Method | Description | Type |
|---|---|---|
resetField |
Reset current field and remove validation result. | () => void |
clearValidate |
Remove validation status of the field. | () => void |