react-final-form

What is react-final-form?

react-final-form is a framework-agnostic form state management library for React. It provides a simple and flexible way to manage form state, validation, and submission handling in React applications.

What are react-final-form's main functionalities?

Form State Management

This feature allows you to manage the state of your form fields. The code sample demonstrates a simple form with two fields, 'firstName' and 'lastName', and a submit button. The form state is managed and displayed in real-time.

const MyForm = () => (
  <Form
    onSubmit={formValues => {
      console.log(formValues);
    }}
    render={({ handleSubmit, form, submitting, pristine, values }) => (
      <form onSubmit={handleSubmit}>
        <div>
          <label>First Name</label>
          <Field name="firstName" component="input" type="text" placeholder="First Name" />
        </div>
        <div>
          <label>Last Name</label>
          <Field name="lastName" component="input" type="text" placeholder="Last Name" />
        </div>
        <div>
          <button type="submit" disabled={submitting || pristine}>
            Submit
          </button>
        </div>
        <pre>{JSON.stringify(values, 0, 2)}</pre>
      </form>
    )}
  />
);

Field-Level Validation

This feature allows you to add validation to individual fields. The code sample shows how to add a 'required' validation to the 'firstName' and 'lastName' fields.

const required = value => (value ? undefined : 'Required');

const MyForm = () => (
  <Form
    onSubmit={formValues => {
      console.log(formValues);
    }}
    render={({ handleSubmit }) => (
      <form onSubmit={handleSubmit}>
        <div>
          <label>First Name</label>
          <Field name="firstName" component="input" type="text" placeholder="First Name" validate={required} />
        </div>
        <div>
          <label>Last Name</label>
          <Field name="lastName" component="input" type="text" placeholder="Last Name" validate={required} />
        </div>
        <div>
          <button type="submit">
            Submit
          </button>
        </div>
      </form>
    )}
  />
);

Form-Level Validation

This feature allows you to add validation to the entire form. The code sample demonstrates how to validate the 'firstName' and 'lastName' fields at the form level.

const validate = values => {
  const errors = {};
  if (!values.firstName) {
    errors.firstName = 'Required';
  }
  if (!values.lastName) {
    errors.lastName = 'Required';
  }
  return errors;
};

const MyForm = () => (
  <Form
    onSubmit={formValues => {
      console.log(formValues);
    }}
    validate={validate}
    render={({ handleSubmit }) => (
      <form onSubmit={handleSubmit}>
        <div>
          <label>First Name</label>
          <Field name="firstName" component="input" type="text" placeholder="First Name" />
        </div>
        <div>
          <label>Last Name</label>
          <Field name="lastName" component="input" type="text" placeholder="Last Name" />
        </div>
        <div>
          <button type="submit">
            Submit
          </button>
        </div>
      </form>
    )}
  />
);

Other packages similar to react-final-form

formik

Formik is a popular form library for React that provides a higher-level API for managing form state, validation, and submission. It is similar to react-final-form but offers more built-in hooks and components for easier integration.

react-hook-form

React Hook Form is a performant, flexible, and extensible form library for React. It uses hooks to manage form state and validation, making it a lightweight alternative to react-final-form with a focus on performance.

redux-form

Redux Form is a form state management library that integrates with Redux. It is similar to react-final-form but is more tightly coupled with Redux, making it suitable for applications that already use Redux for state management.

README

🏁 React Final Form

✅ Zero dependencies (that affect your bundle size)

✅ Only peer dependencies: React and 🏁 Final Form

✅ Opt-in subscriptions - only update on the state you need!

✅ 💥 3.0k gzipped 💥

React Final Form is sponsored by Sencha.

Comprehensive JS framework and UI components for building enterprise-grade web apps.

💬 Give Feedback on React Final Form 💬

In the interest of making 🏁 React Final Form the best library it can be, we'd love your thoughts and feedback.

Take a quick survey.

React Final Form is a thin React wrapper for Final Form, which is a subscriptions-based form state management library that uses the Observer pattern, so only the components that need updating are re-rendered as the form's state changes.

Getting Started

Philosophy

Examples

API

FAQ