The main problem related to React Router lazy loading is that it can cause performance issues if not implemented correctly. Lazy loading can increase the initial page load time, as the code for each component needs to be loaded separately. Additionally, if a component is not used often, it may never be loaded at all, resulting in wasted resources. Finally, there are potential compatibility issues with older browsers that do not support lazy loading.
import React, { Suspense } from 'react';
import { BrowserRouter as Router, Route, Switch } from 'react-router-dom';
const Home = React.lazy(() => import('./Home'));
const About = React.lazy(() => import('./About'));
const Contact = React.lazy(() => import('./Contact'));
function App() {
return (
<Router>
<Suspense fallback={<div>Loading...</div>}>
<Switch>
<Route exact path="/" component={Home} />
<Route path="/about" component={About} />
<Route path="/contact" component={Contact} />
</Switch>
</Suspense>
</Router> ); } export default App;
1. import React, { Suspense } from ‘react’;
// This line imports the React library and the Suspense component from the React library.
2. import { BrowserRouter as Router, Route, Switch } from ‘react-router-dom’;
// This line imports the BrowserRouter, Route and Switch components from the react-router-dom library.
3. const Home = React.lazy(() => import(‘./Home’));
// This line creates a constant called Home that uses the lazy loading feature of React to dynamically import a component called Home from a file in the same directory as this file (the App component).
4. const About = React.lazy(() => import(‘./About’));
// This line creates a constant called About that uses lazy loading to dynamically import a component called About from a file in the same directory as this file (the App component).
const Contact = React.lazy(() => import(‘./Contact’)); // This line creates a constant called Contact that uses lazy loading to dynamically import a component called Contact from a file in the same directory as this file (the App component).
5. function App() { return ( // This is an arrow function which returns JSX code wrapped in Router tag which is imported earlier
6.Loading…
}> //This Suspense tag wraps all our routes with fallback props of Loading… if any route takes time to load
7. //Switch tag will make sure only one route is rendered at once
8. //This Route will render Home Component when exact path “/” is matched
9. //This Route will render About Component when path “/about” is matched
10. //This Route will render Contact Component when path “/contact” is matched ) } export default App; //Finally we close all tags and export our app
Lazy load problem
Lazy loading is a technique used to delay the loading of certain components until they are needed. This can help improve the performance of an application by only loading what is necessary at any given time. However, this can be a problem when using React Router, as it does not support lazy loading out of the box. To work around this issue, developers must manually configure their routes to enable lazy loading. This can involve setting up dynamic imports and code splitting, which can be complex and time-consuming tasks. Additionally, some libraries such as React Loadable may need to be used in order to properly implement lazy loading with React Router.
What is React lazy load
React lazy load is a feature of React Router that allows for the loading of components on demand. This means that instead of loading all components at once, only the necessary components are loaded when needed. This helps to reduce the initial page load time and improve performance. It also allows for better code organization and separation of concerns, as each component can be loaded independently.
How do I use React lazy on my router
React lazy is a feature of React that allows you to dynamically import components. This means that instead of loading all the components upfront, you can load them as needed. This can be useful for optimizing performance in large applications.
In order to use React lazy on your router in React Router, you need to wrap the component you want to lazy-load in a dynamic import call. For example:
const MyComponent = React.lazy(() => import(‘./MyComponent’));
Then, when defining your routes, simply pass the MyComponent component into the Route component like so:
This will cause React Router to dynamically load the MyComponent component when navigating to that route.
