import React from 'react'; import ReactDOM from 'react-dom'; import useForm from 'react-hook-form'; function App() { const { register, errors, handleSubmit } = useForm(); const onSubmit = data => { alert(JSON.stringify(data)); }; return (

{errors.firstName && errors.firstName.message}

{errors.lastName && errors.lastName.message}

{errors.email && errors.email.message}
); } const rootElement = document.getElementById('root'); ReactDOM.render(, rootElement);