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React Lazy and Suspense

Introduction to React
What is React? Advantages of React JSX syntax Setting up the development environment
Components and Props
Components in React Functional Components Class Components Props PropTypes and defaultProps Component composition
State and Lifecycle Methods
State in React setState method Lifecycle Methods in Class Components Conditional Rendering based on the state
Handling Events
Event handling in React Binding Event Handlers Passing Arguments to Event Handlers Conditional Event Handling
Forms and User Input
Forms in React Controlled Components Uncontrolled Components Form Validation
Lists and Keys
Rendering Lists in React Keys Extracting Components with Keys
Components Lifecycle
Understanding Components Lifecycle Mounting, Updating and Unmounting Lifecycle Methods
Working with APIs
Making HTTP Requests with Axios Handling Responses with Promises Asyncawait syntax for making API calls
React Router
What is React Router? Installation Configuring Routes Navigating between pages using Link and NavLink components
Redux State Management
What is Redux Three principles of Redux Redux Store, Actions, and Reducers ReactRedux integration
Styling React Applications
Styling in React Inline styles CSS Modules Styled Components
Testing React Applications
Testing Fundamentals Testing React Components Integration Testing Using Jest and React Testing Library
Deployment and Optimization
Deployment options for React applications Performance Optimization Code Splitting React Lazy and Suspense
Next Steps
Advanced Topics Resources for continued learning Conclusion

React Lazy and Suspense

9

#description

React Lazy and Suspense are both new features introduced in React 16.6 that help to improve the performance of your React applications, especially when you're dealing with large applications that have a lot of components.

React Lazy allows you to easily split your code into smaller chunks, which can be loaded on-demand when the user navigates to a specific route or interacts with a specific component. This helps to reduce the initial load time of your application and improves the user experience.

To use React Lazy, you first need to import the lazy function from the React library. This function accepts a function that returns a dynamic import, which loads the module on-demand.

Here's an example of how to use React Lazy:

 
                    
import React, { lazy, Suspense } from 'react';

const MyComponent = lazy(() => import('./MyComponent'));

function App() {
  return (
    <div>
      <Suspense fallback={<div>Loading...</div>}>
        <MyComponent />
      </Suspense>
    </div>
  );
}

In this example, we're using the lazy function to load the MyComponent module on-demand. We're also using the Suspense component to specify a fallback UI to be rendered while the component is loading.

React Suspense, on the other hand, is a new feature that allows you to suspend rendering until a certain condition is met, such as data being loaded from an API or a dynamic import being completed. This helps to avoid showing an empty or loading state to the user, which can lead to a poor user experience.

To use React Suspense, you need to wrap your component with a Suspense component and provide a fallback UI.

Here's an example:

 
                    
import React, { Suspense } from 'react';

function App() {
  return (
    <div>
      <Suspense fallback={<div>Loading...</div>}>
        <MyComponent />
      </Suspense>
    </div>
  );
}

In this example, we're using the Suspense component to suspend rendering until the MyComponent module has completed loading. We're also specifying a fallback UI to be rendered while the component is loading.

Overall, React Lazy and Suspense are powerful tools that can help you to improve the performance of your React applications by reducing the initial load time and avoiding showing empty or loading states to the user.

March 25, 2023

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