ui/docs/content/3.components/form.md

description, category, links

description	category	links
A form component with built-in validation and submission handling.	form	label icon to GitHub i-simple-icons-github https://github.com/nuxt/ui/tree/v3/src/runtime/components/Form.vue

Usage

Use the Form component to validate form data using validation libraries such as Valibot, Zod, Yup, Joi, Superstruct or your own validation logic.

It works with the FormField component to display error messages around form elements automatically.

Schema Validation

It requires two props:

• state - a reactive object holding the form's state.
• schema - any Standard Schema or a schema from Yup, Joi or Superstruct.

::warning No validation library is included by default, ensure you install the one you need. ::

::tabs ::component-example

name: 'form-example-valibot' props: class: 'w-60'

::

::component-example

name: 'form-example-zod' props: class: 'w-60'

::

::component-example

name: 'form-example-yup' props: class: 'w-60'

::

::component-example

name: 'form-example-joi' props: class: 'w-60'

::

::component-example

name: 'form-example-superstruct' props: class: 'w-60'

:: ::

Errors are reported directly to the FormField component based on the name or error-pattern prop. This means the validation rules defined for the email attribute in your schema will be applied to <FormField name="email">{lang="vue"}.

Nested validation rules are handled using dot notation. For example, a rule like { user: z.object({ email: z.string() }) }{lang="ts"} will be applied to <FormField name="user.email">{lang="vue"}.

Custom Validation

Use the validate prop to apply your own validation logic.

The validation function must return a list of errors with the following attributes:

• message - the error message to display.
• name - the name of the FormField to send the error to.

::tip It can be used alongside the schema prop to handle complex use cases. ::

::component-example

name: 'form-example-basic' props: class: 'w-60'

::

Input Events

The Form component automatically triggers validation when an input emits an input, change, or blur event.

• Validation on input occurs as you type.
• Validation on change occurs when you commit to a value.
• Validation on blur happens when an input loses focus.

You can control when validation happens this using the validate-on prop.

::component-example

source: false name: 'form-example-elements' options:

• name: 'validate-on' label: 'validate-on' items:
  • 'input'
  • 'change'
  • 'blur' default:
  • 'input'
  • 'change'
  • 'blur' multiple: true

---

::

::tip You can use the useFormField composable to implement this inside your own components. ::

Error Event

You can listen to the @error event to handle errors. This event is triggered when the form is submitted and contains an array of FormError objects with the following fields:

• id - the input's id.
• name - the name of the FormField
• message - the error message to display.

Here's an example that focuses the first input element with an error after the form is submitted:

::component-example

name: 'form-example-on-error' collapse: true props: class: 'w-60'

::

Nesting Forms

Nesting form components allows you to manage complex data structures, such as lists or conditional fields, more efficiently.

For example, it can be used to dynamically add fields based on user's input: ::component-example

collapse: true name: 'form-example-nested'

::

Or to validate list inputs: ::component-example

collapse: true name: 'form-example-nested-list'

::

API

Props

:component-props

Slots

:component-slots

Emits

:component-emits

Expose

You can access the typed component instance using useTemplateRef.

<script setup lang="ts">
const form = useTemplateRef('form')
</script>

<template>
  <UForm ref="form" />
</template>

This will give you access to the following:

Name	Type
submit(){lang="ts-type"}	Promise<void>{lang="ts-type"} Triggers form submission.
validate(opts: { name?: keyof T | (keyof T)[], silent?: boolean, nested?: boolean, transform?: boolean }){lang="ts-type"}	Promise<T>{lang="ts-type"} Triggers form validation. Will raise any errors unless opts.silent is set to true.
clear(path?: keyof T){lang="ts-type"}	void Clears form errors associated with a specific path. If no path is provided, clears all form errors.
getErrors(path?: keyof T){lang="ts-type"}	FormError[]{lang="ts-type"} Retrieves form errors associated with a specific path. If no path is provided, returns all form errors.
setErrors(errors: FormError[], name?: keyof T){lang="ts-type"}	void Sets form errors for a given path. If no path is provided, overrides all errors.
errors{lang="ts-type"}	Ref<FormError[]>{lang="ts-type"} A reference to the array containing validation errors. Use this to access or manipulate the error information.
disabled{lang="ts-type"}	Ref<boolean>{lang="ts-type"}
dirty{lang="ts-type"}	Ref<boolean>{lang="ts-type"} true if at least one form field has been updated by the user.
dirtyFields{lang="ts-type"}	DeepReadonly<Set<keyof T>>{lang="ts-type"} Tracks fields that have been modified by the user.
touchedFields{lang="ts-type"}	DeepReadonly<Set<keyof T>>{lang="ts-type"} Tracks fields that the user interacted with.
blurredFields{lang="ts-type"}	DeepReadonly<Set<keyof T>>{lang="ts-type"} Tracks fields blurred by the user.

Theme

:component-theme