Getting Started With redux-form

redux-form primarily consists of three things:

1. A Redux reducer that listens to dispatched redux-form actions to maintain your form state in Redux.
2. A React component decorator that wraps your entire form in a Higher Order Component (HOC) and provides functionality via props.
3. A Field component to connect your individual field inputs to the Redux store.

Implementation Guide

Step #1

The first thing that you have to do is to give the redux-form reducer to Redux. You will only have to do this once, no matter how many form components your app uses.

import { createStore, combineReducers } from 'redux'
import { reducer as formReducer } from 'redux-form'

const reducers = {
  // ... your other reducers here ...
  form: formReducer     // <---- Mounted at 'form'
}
const reducer = combineReducers(reducers)
const store = createStore(reducer)

Step #2

Decorate your form component with reduxForm(). This will provide your component with props that provide information about form state and functions to submit your form.

Each input component must be placed inside the component prop of a Field component. The Field component will pass props such as value, onChange, onBlur, etc. to the React.DOM.input component to populate its value and listen for changes.

import React, { Component } from 'react';
import { Field, reduxForm } from 'redux-form';

class ContactForm extends Component {
  render() {
    const { handleSubmit } = this.props;
    return (
      <form onSubmit={handleSubmit}>
        <div>
          <label>First Name</label>
          <Field name="firstName" component="input" type="text"/>
        </div>
        <div>
          <label>Last Name</label>
          <Field name="lastName" component="input" type="text"/>
        </div>
        <div>
          <label>Email</label>
          <Field name="email" component="input" type="email"/>
        </div>
        <button type="submit">Submit</button>
      </form>
    );
  }
}

// Decorate the form component
ContactForm = reduxForm({
  form: 'contact' // a unique name for this form
})(ContactForm);

export default ContactForm;

You're done!

That's it! There is no Step #3!

If you're starting out with redux-form, a good place to continue learning about how to connect up the inputs to redux-form would be the Simple Form Example.