vdux-form

vdux form component

Usage no npm install needed!

<script type="module">
  import vduxForm from 'https://cdn.skypack.dev/vdux-form';
</script>

README

form

js-standard-style

vdux form component

Installation

$ npm install vdux-form

Usage

API - props

  • onSubmit - Handles a form submission. Receives the contents of the form, serialized to JSON, and casted by cast (if specified).
  • validate - Validate the JSON contents of the form. Blocks onSubmit if not valid. Refer to the validation section for more details.
  • cast - Before being validated you can transform the model with this. It should accept a model and return a new model.
  • loading - Whether or not the form is currently loading. If true, submits will be disabled. Defaults to false.
  • transformError - Transform an error response from your onSubmit function into a form that is consumable by vdux-form. A default can be specified using setTransformError.
  • onSuccess - Run if onSubmit succeeds; receives the result as its first argument
  • onFailure - Run if onSubmit throws an error; receives the error as its first argument

Validation

Your validate function should accept a model and return an object of the form:

{valid: Boolean, errors: [Errors]}

If valid is false, errors should include a list of invalid fields. Each error entry should have the form:

{field, message}

Where field is the name attribute of the form field that the message applies to. Your message will then be set on the appropriate field using setCustomValidity. This will trigger an invalid event on that form field, which you can capture on the input.

Example

import Form from 'vdux-form'

function render () {
  return (
    <Form validate={validate}>
      <input name='username' onInvalid={e => setError(e.target.validationMessage)} />
      {
        error && <span class='error'>{error}</span>
      }
    </Form>
  )
}

function validate ({username}) {
  if (username.length < 3) {
    return {
      valid: false,
      errors: [{field: 'username', message: 'Username must be at least 3 characters long'}]
    }
  }

  return {
    valid: true
  }
}

Error handling

You can specify a default transform for your errors like this:

import Form from 'vdux-form'

Form.setTransformError(err => ({
  if (err.status === 400) {
    return err.errors
  }
}))

License

MIT