Overview

React 19 Course Overview

Introducing React 19 version, designed to streamline the process of building websites and apps, making it both easier and more efficient. Packed with exciting features such as the React Compiler, Actions API, and enhanced Hooks functionality, coding becomes faster and managing your application's data is more straightforward than ever.

React 19 version majorly delaing with following concepts:

1. React Compiler:

The React Compiler is a significant tool in the React ecosystem, responsible for changing React code into optimized JavaScript that can effectively run in the browser. It takes JSX, a syntax extension for JavaScript frequently utilized with React, and changes over it into regular JavaScript that browsers can understand. Additionally, the compiler may apply different optimizations such as dead code end, code part, and tree shaking to upgrade execution and diminish bundle size. The Respond team continuously improves the compiler to guarantee that React applications are quick and efficient.

2. Server Components:

Server Components in React are a groundbreaking feature designed to bridge the gap between frontend and backend development. With Server Components, developers can write components that render both on the server and in the browser. This approach offers several benefits, including improved performance, better SEO, and enhanced code sharing between frontend and backend. Server Components enable developers to build highly interactive applications while still leveraging the power of server-side rendering.

3. Actions:

In the context of React applications, actions refer to the events or triggers that start changes in the application's state. Actions are ordinarily dispatched by components or other parts of the application and are at that point processed by reducers to update the state. Actions are defined as plain JavaScript objects with a type property that describes the action and extra data payload if essential. By using actions, developers can manage application state in a predictable and efficient manner, making it easier to keep up and debug complex applications.

4. Document Metadata:

Document metadata in React applications refers to the information associated with the HTML document that is not visible on the page but provides essential details for search engines, social media platforms, and browser behavior. This metadata includes elements such as the document's title, description, author, and any other relevant information that helps browsers and web crawlers understand the content of the page. React developers often utilize libraries like React Helmet to dynamically update document metadata based on the current application state or user interactions.

5. Asset Loading:

Asset loading is a critical aspect of web development, especially in React applications where efficient loading of JavaScript, CSS, images, and other resources is essential for optimal performance. React provides various mechanisms for loading assets, including dynamic imports, webpack's file-loader, and tools like React Loadable for code splitting. By strategically loading assets, developers can reduce initial page load times, improve perceived performance, and prioritize essential resources for faster rendering and interactivity.

6. Web Components Integration:

React provides seamless integration with Web Components, enabling developers to use them alongside native React components within the same application. This integration allows for interoperability between React and Web Components, empowering developers to leverage the strengths of both technologies in their projects. With Web Components integration, developers can extend React applications with third-party components or gradually migrate existing codebases to embrace emerging web standards.

7. Enhanced Hooks:

React Hooks revolutionized state management and side effects in React functional components. Enhanced Hooks build upon this foundation by providing additional capabilities and optimizations for common use cases. These improved hooks may include features such as sluggish initialization, memoization, and error handling, permitting developers to write more concise, effective, and viable code. By leveraging enhanced hooks, developers can streamline their React components, improve performance, and upgrade the overall developer experience.

React 19 Online Taining
Key Points

Real Time Expert Trainers                       Project Scenarios Explained                              Flexible Learning Options
Gain knowledge from industry                  Complete projects and exercises                        Select anywhere, as class room & 
experts with 10 years experience             that are designed to help you develop               self-paced training are both readily
 in live projects.                                          skills in a realistic environment.                           available.
    

Interactive doubt sessions                        Industry Ready Curriculum                               Interview & Job Support
Our digitally interactive hands                    We have designed our curriculum to                  Get career guidance,  prepare for
on training, making your learning               cover all of the topics in React JS                       interviews and secure your
  active and memorable.                              from the basic level to an advanced level.         Dream Job

Community Driven Learning                    Flexible Payment Options                                 Making you job ready
When you network with experts                Our pricing visualization is one                          Core objective of React Training in 
in the field, building a community              of the most affordable offering                          Hyderabad: We have structured 
is more than networking                             some very flexible payment options                  this course to help the candidates
opportunities beyond                                  compared to our competition.                           become Job ready in a market  
stgdbdfnghb                                                    

What’s new in React 19

Actions

One of the most common use cases in React apps is you want to mutate some data and update state after that. Meaning you can make an api request when a user submits form to change his/her name and then handle the response You used to have to manage those yourself - pending states, error etc... Until now you would only need store your piece of state without worrying about optimistic updates or multiple mutually exclusive requests which will fail for the ones not arriving first.

Actions: Functions that trigger async transitions by convention

Here is an example of how Actions takes care of sending data for you to the database automatically:

Actions: Actions give you a pending state that is initialized at the start of each request and automatically cleared when reaching finalized states on commits.

Optimistic updates:  New use Optimistic hook provides action means for actions in order to display instantaneous changes while requests submit.

Error Handling: Actions provide optional error handling for you to use and automatically roll back optimistic updates when a request fails.

Forms: elements can now take functions as the action and formAction props. Actions - Passing functions to the action props use Actions by default, and resetForm automatically after submission

On top of that, React introduced useOptimistic for optimistic updates and React. 19 as a new hook (React.optimistic) A better way of handling some common cases for Actions using useActionState. We adding form actions open source in react-dom and use it to manage forms automatically, also we add useFormStatus by support the common cases for Actions on forms.

React DOM: Actions

React 19 also has new features for react-dom and they are into the Actions. Support passing functions as the action and formAction props for , and button: to allow forms automatic submission with Actions 

For uncontrolled components with a Action, when the action is successful React will reset the form for you. You can trigger form reset manually: you need to call new requestFormReset React DOM API.

Learn more about the react-dom ,<form>, <input>, and <button>.

react-dom : New hook: useFormStatus

Design systems frequently require you to write design components that need access information about the  <form> they are in without drilling props down . Using Context, we can achieve this but to make the common-case easier, We have added a new use Form Status:

Creating Request for Server Components

The React Server Components in React 19  are stable and do not break between major versions, but the APIs they rely on to create a bundler or framework for those components will avoid semver at all cost and should be used with caution:APIs may change without warning! 

We recommend either pinning to a specific React version or using the Canary release if you need an advanced bundler or framework to support sophomore components. In the future, we will keep collaborating with bundlers and frameworks on making more APIs stable that are used internally to enable React Server Components.

Server Actions

A Client Component can call async functions ( which will be executed on the server) using Server Actions.

In a framework that supports it (e.g., re-frame and Fulcro), when you define a Server Action with the :use dspec, your framework of choice will automatically provide an occurrence for the server function, and pass this to Client Components. And then, when that function is called on the client side, React will make a request to the server in order to run this function and return its result.

With React 19, We can stop using:

• useMemo() hook and memo() higher order function
• useCallback() hook              
• useContext() hook
• forwardRed() Hook
• Context.Provider
• React.lazy