In this blog post, we will learn how to create a custom useNetworkStatus hook in React for checking the network status of our application. This hook will allow us to easily check whether the user is online or offline, and take appropriate actions based on the network status.

Table of Contents

• Introduction
• Prerequisites
• Implementing the useNetworkStatus Hook
• Using the useNetworkStatus Hook
• Conclusion

Introduction

When building web applications, it’s important to handle network connectivity gracefully. By knowing the network status, we can provide a better user experience by showing appropriate messages or adapting the functionality of our application.

Prerequisites

To follow along with this tutorial, you should have a basic understanding of React and hooks. If you are not familiar with hooks, I recommend checking out the React Hooks documentation before proceeding.

Implementing the useNetworkStatus Hook

Let’s start by creating a new file named useNetworkStatus.js. Inside this file, we will define our custom hook.

import { useEffect, useState } from 'react';

const useNetworkStatus = () => {
  const [isOnline, setIsOnline] = useState(navigator.onLine);

  useEffect(() => {
    const handleOnline = () => {
      setIsOnline(true);
    };

    const handleOffline = () => {
      setIsOnline(false);
    };

    window.addEventListener('online', handleOnline);
    window.addEventListener('offline', handleOffline);

    return () => {
      window.removeEventListener('online', handleOnline);
      window.removeEventListener('offline', handleOffline);
    };
  }, []);

  return isOnline;
};

export default useNetworkStatus;

Let’s go through the implementation step by step:

1. We import the necessary hooks from React.
2. Inside our custom hook, we create a state variable isOnline and set its initial value based on navigator.onLine.
3. We use useEffect to add event listeners for the 'online' and 'offline' events. When these events occur, we update the isOnline state accordingly.
4. Lastly, we clean up the event listeners when the component unmounts by returning a cleanup function from useEffect.

Using the useNetworkStatus Hook

Now that we have implemented our custom hook, let’s see how we can use it in our components.

import React from 'react';
import useNetworkStatus from './useNetworkStatus';

const App = () => {
  const isOnline = useNetworkStatus();

  return (
    <div>
      {isOnline ? (
        <p>You are online</p>
      ) : (
        <p>You are offline</p>
      )}
    </div>
  );
};

export default App;

We import the useNetworkStatus hook in our component and use it to get the isOnline status. Based on the isOnline value, we display appropriate messages to the user.

Conclusion

In this tutorial, we learned how to create a custom useNetworkStatus hook in React for checking the network status of our application. By using this hook, we can easily handle different network conditions and provide a better user experience.