Key Differences Between React Hook Form and Formik

What are the advantages of React Hook Form over Formik and Redux Form?

React Hook Form provides a simple way to handle form state and validation without Redux or external state management. It uses uncontrolled components for better performance with less re-renders. Validation and error handling is simple with register, handleSubmit, and errors.

How does React Hook Form handle validation?

React Hook Form supports validation attributes like required, min, max etc on inputs registered with register. It also supports schema validation by passing a Yup schema to useForm.

How does React Hook Form handle uncontrolled components?

The register hook is passed to the ref of each uncontrolled input. This makes the value available for validation and submission. A name attribute is required on each input for register.

What are some disadvantages of Formik?

Struggles with complex multi-step forms
Not intuitive for wizard forms
Updating Redux store not easy
Tricky to handle nested inputs with own validation

How can I use React Hook Form with Material UI components?

Use the Controller component to wrap Material UI inputs. It provides field and fieldState props to control the input. Pass error prop as !!error to convert to boolean.

What are some key differences between Controlled and Uncontrolled inputs?

Controlled inputs have value and onChange props to control value
Uncontrolled use ref to get input values
Formik only supports Controlled but React Hook Form supports both

How does the !! operator work in JavaScript?

The !! operator converts a value to its boolean equivalent. Falsy values like 0, null, undefined etc become false. Everything else becomes true.

Where can I find the validation rules supported by React Hook Form?

The validation rules like required, min, max etc are standard HTML validation attributes. See MDN docs for full list.

How can I customize the validation error messages in React Hook Form?

Pass a validate function to register to return a custom validation error message.

validate: value => value !== 'test' ? 'Error message' : true

How does Yup schema validation work with React Hook Form?

Pass a Yup schema object to useForm config. Yup provides chainable validation functions to build complex schemas.

const schema = yup.object().shape({
  name: yup.string().required(),
  age: yup.number().positive() 
});

useForm({
  resolver: yupResolver(schema)
})

ref: