Random

Posted on Dec 8 • Originally published at Medium

React 19 is now stable ! What’s New 👇

#webdev #javascript #react #programming

React 19 has arrived with exciting new features and improvements!

Hello Dev’s its me Md Taqui Imam, The React 19 is now stable so let’s explore what’s new and how you can use these features in your projects.

This guide will walk you through the most important updates with practical examples.

Follow me in Github⭐

Actions and Form Handling ⭐

Actions are one of the biggest additions in React 19. They make it easier to handle form submissions and data mutations.

function UpdateProfile() {
 const [error, submitAction, isPending] = useActionState(
 async (previousState, formData) => {
 const name = formData.get("name");
 try {
 await updateProfile(name);
 return null; // No error
 } catch (err) {
 return "Failed to update profile";
 }
 },
 null
 );
return (
 <form action={submitAction}>
 <input type="text" name="name" />
 <button type="submit" disabled={isPending}>
 {isPending ? "Updating…" : "Update Profile"}
 </button>
 {error && <p className="error">{error}</p>}
 </form>
 );
}

Using Form Status 🟢

The new useFormStatus hook makes it easy to show loading states:

import { useFormStatus } from 'react-dom';
function SubmitButton() {
 const { pending } = useFormStatus();

 return (
 <button disabled={pending}>
 {pending ? 'Submitting…' : 'Submit'}
 </button>
 );
}

New Hooks 🎉

1. useOptimistic 🆕
This hook helps create instant feedback while waiting for server responses:

import { use } from 'react';
function UserProfile({ userPromise }) {
 const user = use(userPromise);

 return (
 <div>
 <h1>{user.name}</h1>
 <p>{user.email}</p>
 </div>
 );
}

Document Metadata Support

React 19 now supports metadata tags natively:

function BlogPost({ post }) {
 return (
 <article>
 <title>{post.title}</title>
 <meta name="description" content={post.summary} />
 <link rel="canonical" href={post.url} />

 <h1>{post.title}</h1>
 <p>{post.content}</p>
 </article>
 );
}

Asset Loading Improvements

New APIs for optimizing resource loading:

import { preload, preinit, preconnect } from 'react-dom';
function App() {
 // Preload important resources
 preload('/fonts/main.woff2', { as: 'font' });
 preinit('/styles/critical.css', { as: 'style' });
 preconnect('https://api.example.com');
return <Main />;
}

Web Components Support

React 19 now fully supports custom elements:

function App() {
 return (
 <div>
 <custom-element
 stringProp="hello"
 numberProp={42}
 objectProp={{ foo: 'bar' }}
 onCustomEvent={(e) => console.log(e.detail)}
 />
 </div>
 );
}

Other Improvements 🛠️

Ref as a Prop

// Old way with forwardRef
const OldInput = forwardRef((props, ref) => (
 <input ref={ref} {…props} />
));
// New way in React 19
function NewInput({ ref, …props }) {
 return <input ref={ref} {…props} />;
}

Better Error Reporting 🔥

React 19 provides clearer error messages and better hydration error reporting:

const root = createRoot(container, {
 onCaughtError: (error) => {
 // Handle errors caught by Error Boundaries
 logError(error);
 },
 onUncaughtError: (error) => {
 // Handle errors not caught by Error Boundaries
 reportFatalError(error);
 }
});

Conclusion / That’s it 😅

React 19 brings many exciting features that make development easier and more efficient. The new form handling capabilities, hooks, and improved asset loading will help developers build better applications with less code.

Remember that while these features are now stable, it’s recommended to test thoroughly when upgrading existing applications to React 19.

For more information, check out the official React 19 announcement and documentation.

And see you in next blog post, till then Byy, Have a Nice Day.

Happy coding!

Random

I'm a self-taught Web developer who is always learning and creating cool Project stuffs.

Top comments (18)

Monty • Dec 8

Thanks Dude for the update 🙏

John bobby • Dec 8

👍

Random • Dec 8

You'r welcome 🙌

Sirineo Barila • Dec 8

I didn't have time to digest react 18 and the 19 version is already out. Too #FastTech?

Random • Dec 9

Tech moves at lightning speed these days

Sirineo Barila • Dec 9

Agreed with that!
By the way I reviewed your GitHub profile and it there is this fun link to one of your project that allow to see how valuation of a developer? I think is pretty good, thought you might want to add social sharing capabilities (linkedin, Reddit...) and an error is thrown when trying to download the image after valuation saying that user have reached the daily download quota.