Rendering Elements in ReactJs

Purpose of Render

The purpose of the render function in ReactJS is to define what elements or components should be displayed on the user interface based on the current state and props of a component. It acts as a blueprint, ensuring the visual representation of the data is accurate. By calling the render method, React knows how to update the DOM efficiently when changes occur, ensuring the application reflects the latest data or state in real-time.

Importance of Render in ReactJS

• Efficient UI Updates: The render method ensures that only the necessary parts of the user interface are updated, preventing unnecessary re-rendering of the entire DOM.
   
• Dynamic Content: It allows dynamic content to be displayed based on changing states or props, ensuring that user interactions reflect immediately on the interface.
   
• Optimization via Virtual DOM: React's render process uses the virtual DOM to compare changes, allowing for faster updates and improving application performance.
   
• Modularity: Components can be reused and rendered independently, promoting clean and maintainable code.
   
• Enhanced User Experience: Efficient rendering provides a smoother, more responsive experience for users without page reloads.

How to perform Rendering in React?

Let’s discuss Rendering in React using an example of a component and work our way accordingly in the article to render elements.

In the example we will consider a root id of an id tag and Rendering in React it accordingly, 

All the elements in this tag are considered as the root element in the React DOM. Everything in this div is regarded as a root. 

Most of the time, React Applications are built using a single root DOM, but when we try to integrate React into a pre-existing application, we can isolate as many root nodes as we want in the DOM.

For your reference, we have added an example below, 

Using the above HTML and React code, the final output would be:

OUTPUT

Click on the following link to read further: Hooks in React JS

Updation in ReactJs Elements(Rendering in React after updation)

One of the critical features of React DOM is that it compares the elements and their children to the previous values and only updates the DOM if there are changes applied. What would happen if we had rendered the elements once but performed the changes in the app? Will the app render itself again? 

Using Rendering in React, the events are immutable. This means that the DOM creates a new element for a recent change whenever a change is applied. To understand the concept better, go through the live clock code given below, 

OUTPUT

In the above code, we have used a few ReactJs methods. The ReactDOM.render() is called every second from the setInterval() callback. 

In the above example, we have seen that the ReactDOM.render() method renders the elements on the browser window, using two arguments(the HTML code and the HTML element).

Also See, Dropdown in React JS 

Example of Using Render in React JS

In ReactJS, the render() method is used to specify what the UI should look like. Let’s look at a simple example where we render a component that displays a greeting message.

• JavaScript

JavaScript

import React from 'react';
import ReactDOM from 'react-dom';

// Creating a React component
class Greeting extends React.Component {
  render() {
    return (
      <div>
        <h1>Hello, Welcome to React!</h1>
        <p>This message is rendered using the render() method.</p>
      </div>
    );
  }
}

// Rendering the component to the DOM
ReactDOM.render(<Greeting />, document.getElementById('root'));

You can also try this code with Online Javascript Compiler

Run Code

Output

Frequently Asked Questions

What is the render() method in ReactJs?

The render() method in ReactJs is used to specify the content that is to be displayed on the website. It is used to describe the view which is finally rendered on the browser. The render method is also used to perform Rendering in React content on the public folder where the index.html file is located in the folder. This makes our content visible on screen. 

Does changing state re-render the React Application?

React components automatically re-render whenever we perform a change in the application’s state or props. A simple update of the condition causes the entire User Interface (UI) elements to be re-rendered automatically from anywhere in the code. This is done only by the render method provided by the ReactDOM. 

Can we have multiple ReactDOM renders?

Yes, we can have multiple renders using the ReactDOM. We can have multiple calls to ReactDOM. render() in a single JavaScript file without any issues. We can have multiple calls to ReactDOM. render() may be especially useful when using React in an existing application/site.

What is the difference between render and return in React?

In React, the render() method is responsible for defining the UI and updating the DOM, while return specifies what the render() method should output (typically JSX). The render() method encloses the return statement.

Conclusion

This article has covered all the essential information about Rendering Elements in ReactJS.he render() method in ReactJs is used to specify the content to be displayed on the website. It is used to describe the view which is finally rendered on the browser. The render method also renders our content on the public folder where the index.html file is located in the folder. This makes our content visible on screen. The article covers the ways using which we can Rendering in React the elements. It also explains the update of ReactJs Elements after the app is rendered. Did you have fun exploring ReactJs?

Recommended Readings:

• For Loop in React JS

You can also consider our React Js Course to give your career an edge over others.  

Happy Learning Ninjas!