Form handling in React without states

Handling forms in React is typically done by storing the values of the form fields in state. For example:\

import * as React from 'react'

function ExampleForm() {
	const [firstName, setFirstName] = React.useState('')
	const [lastName, setLastName] = React.useState('')

	function handleSubmit(e) {
		e.preventDefault()
		// Do something with the data
	}

	return (
		<form onSubmit={handleSubmit}>
			<input
				type="text"
				name="firstName"
				value={firstName}
				onChange={(e) => setFirstName(e.target.value)}
			/>
			<input
				type="text"
				name="lastName"
				value={lastName}
				onChange={(e) => setLastName(e.target.value)}
			/>
			<button type="submit">Submit</button>
		</form>
	)
}

The browser has a built-in API called FormData that makes it easy to get the data from a form. Even if you're using React, FormData simplifies the process of obtaining the data, without needing to manage the state of each input.

import * as React from 'react'

function ExampleForm() {
	function handleSubmit(e) {
		e.preventDefault()
		const formData = new FormData(e.target)
		const firstName = formData.get('firstName')
		const lastName = formData.get('lastName')
		// Do something with the data
	}

	return (
		<form onSubmit={handleSubmit}>
			<input type="text" name="firstName" />
			<input type="text" name="lastName" />
			<button type="submit">Submit</button>
		</form>
	)
}

FormData is also a Request body type for the Fetch API. If you're using an edge function to handle form submissions, you can use FormData to quickly obtain the data from the request.

function handleRequest(request) {
  const formData = await request.formData()
  const firstName = formData.get('firstName')
  const lastName = formData.get('lastName')
  // Do something with the data
}