newforms

Isomorphic form-handling for React

Programming language: JavaScript

License: GNU General Public License v3.0 or later

Tags: Code Design     Form Logic     React     React-component     Input     Isomorphic     Validation     Form-handling     Forms     Conversion     Coercion    

Latest version: v0.13.2

README

newforms

An isomorphic form-handling library for React.

(Formerly a direct port of the Django framework's django.forms library)

Other React Form Libraries

• react-formal - uses a schema and leverages React's context feature to make it really simple to render fields and error messages

• redux-form - manages form state for you, leaving you do the rendering exactly as you wish

Getting newforms

Node.js

Newforms can be used on the server, or bundled for the client using an npm-compatible packaging system such as Browserify or webpack.

npm install newforms

var forms = require('newforms')

By default, newforms will be in development mode. To use it in production mode, set the environment variable NODE_ENV to 'production' when bundling. To completely remove all development mode code, use a minifier that performs dead-code elimination, such as UglifyJS.

Browser bundle

The browser bundle exposes a global forms variable and expects to find global React variable to work with.

The uncompressed bundle is in development mode, so will log warnings about potential mistakes.

You can find it in the /dist directory.

Upgrade Guide

Documentation @ ReadTheDocs

Newforms Examples @ GitHub

Related Projects

• newforms-bootstrap - Bootstrap 3 integration & grid form form layout components.

• newforms-gridforms - Grid Forms form layout components.

Quick Guide

A quick introduction to defining and using newforms Form objects.

Design your Form

The starting point for defining your own forms is Form.extend().

Here's a simple (but incomplete!) definition of a type of Form you've probably seen dozens of times:

var SignupForm = forms.Form.extend({
  username: forms.CharField(),
  email: forms.EmailField(),
  password: forms.CharField({widget: forms.PasswordInput}),
  confirmPassword: forms.CharField({widget: forms.PasswordInput}),
  acceptTerms: forms.BooleanField({required: true})
})

A piece of user input data is represented by a Field, groups of related Fields are held in a Form and a form input which will be displayed to the user is represented by a Widget. Every Field has a default Widget, which can be overridden.

Rendering a Form

Forms provide helpers for rendering labels, user inputs and validation errors for their fields. To get you started quickly, newforms provides a React component which use these helpers to render a basic form structure.

At the very least, you must wrap rendered form contents in a <form>, provide form controls such as a submit button and hook up handling of form submission:

var Signup = React.createClass({
  render: function() {
    return <form onSubmit={this._onSubmit}>
      <forms.RenderForm form={SignupForm} ref="signupForm"/>
      <button>Sign Up</button>
    </form>
  },

  // ...

Rendering helpers attach event handlers to the inputs they render, so getting user input data is handled for you.

The RenderForm component handles creating a form instance for you, and setting up automatic validation of user input as it's given.

To access this form instance later, make sure the component has a ref name.

Handling form submission

The final step in using a Form is validating when the user attempts to submit.

First, use the ref name you defined earlier to get the form instance via the RenderForm component's getForm() method.

Then call the form's validate() method to ensure every field in the form is validated against its current user input.

If a Form is valid, it will have a cleanedData object containing validated data, coerced to the appropriate JavaScript data type when appropriate:

  propTypes: {
    onSignup: React.PropTypes.func.isRequired
  },

  _onSubmit: function(e) {
    e.preventDefault()

    var form = this.refs.signupForm.getForm()
    var isValid = form.validate()
    if (isValid) {
      this.props.onSignup(form.cleanedData)
    }
  }
})

Implementing custom validation

There's an obvious validation not being handled by our form: what if the passwords don't match?

This is a cross-field validation. To implement custom, cross-field validation add a clean() method to the Form definition:

clean: function() {
  if (this.cleanedData.password &&
      this.cleanedData.confirmPassword &&
      this.cleanedData.password != this.cleanedData.confirmPassword) {
    throw forms.ValidationError('Passwords do not match.')
  }
}

Live Quickstart Demo

MIT Licensed