How to Lazy Load Images in React

If you're a programmer, you know that one of the keys to efficiency is laziness. And when it comes to loading images in React, there's no reason to be anything other than lazy.

With lazy loading, your images will only load when they're needed, which can save you time and bandwidth. In this blog post, we'll show you how to lazy load images in React.

Whether you're just getting started with React or you're a seasoned pro, this should be a quick and easy guide for you.

What is lazy loading?

Lazy loading is an important web development technique that can have a significant impact on the performance of your website and the experience of your users. It works by only loading content when it is needed, rather than all at once upon page load. That way, visitors quickly begin interacting with your site instead of waiting; not to mention, your pages also won't be overloaded with heavy objects that don't need to be there in the first place.

Sites with lazy loading are also beneficial for search engine optimization since bots won't have to crawl excess code or graphics right away. Whether you're a web developer or simply curious about how things work under-the-hood, it’s worth learning more about lazy loading.

How to lazy load images in React using react-lazy-load-image-component

If you're using React, one of the best ways to optimize loading speeds on websites and apps is by lazy loading images. Luckily, it's easy to do with react-lazy-load-image-component. All you need to do is add the lazy load component and a placeholder. Then, wherever you want an image to appear, just use the provided <LazyLoadImage> tag in-place of <img> tags and your work is done!

That way, when the user opens up your page, only low resolution versions of the images are loaded first — saving time and data. Once the user scrolls down to where full resolution versions of the images would appear, they will be loaded automatically in a fraction of a second.

Step 1 – Install React Lazy Load Image Component

Installing react-lazy-load-image-component is a very simple and straightforward process. First, you need to use the npm package manager and install the library with the command 'npm install react-lazy-load-image-component'. This will add the necessary files to your project and make them available for import.

// yarn
$ yarn add react-lazy-load-image-component

// npm
$ npm i --save react-lazy-load-image-component

Step 2 – Import the component

The next step after installing react-lazy-load-image-component is to import the component into your project. To do this, you need to add a line of code that will tell your application where to find the components it needs.

import { LazyLoadImage } from "react-lazy-load-image-component";
import Image from "../images/large.jpg";
import Placeholder from "../images/placeholder.jpg";

Step 3 – Using the LazyLoadImage component

To use the LazyLoadImage component, you first need to wrap the desired image in the <LazyLoadImage> tag, then specify a placeholder (such as a low-resolution version of the original image) and set the actual source of the image.

This way, when a user opens up your page, they will only be presented with the placeholder image first — saving on both time and data.

// Image with a placeholder
<LazyLoadImage
  src={Image}
  alt="My large image"
  placeholderSrc={Placeholder}
/>

Conclusion

Lazy loading images in React can be a simple way to improve the performance of your website or app and provide a better user experience. By using the react-lazy-load-image-component library, you can easily implement lazy loading into your project with just a few lines of code.