React Hooks: useContext

1. Introduction

The `useContext` hook is a powerful feature in React that allows you to manage global state without the need for prop drilling. By using `useContext`, you can share values across your component tree without having to pass props down manually at every level.

2. Understanding useContext

The `useContext` hook is used to consume a context that has been created using `React.createContext()`. Here’s a breakdown of the key components:

• Context Provider: A component that provides the context value to its children.
• Context Consumer: A component that consumes the context value, which can be done using the `useContext` hook.

Creating a Context

const MyContext = React.createContext();

Using useContext

const contextValue = useContext(MyContext);

3. Step-by-Step Usage

To effectively use `useContext`, follow these steps:

1. Create a context using `React.createContext()`.
2. Wrap your component tree with the Context Provider and pass a value prop.
3. Use the `useContext` hook in any functional component to access the context value.

Example Code

import React, { createContext, useContext, useState } from 'react';

// Create a Context
const MyContext = createContext();

const MyProvider = ({ children }) => {
    const [value, setValue] = useState('Hello, World!');
    
    return (
        
            {children}
        
    );
};

const MyComponent = () => {
    const { value, setValue } = useContext(MyContext);
    
    return (
        

            
{value}
             setValue('Hello, React!')}>Change Value
        
    );
};

const App = () => (
    
        
    
);

export default App;

4. Best Practices

To make the most out of `useContext`, consider the following best practices:

• Keep the context value stable by using `useMemo` to prevent unnecessary re-renders.
• Limit the number of context values to avoid complexity; consider splitting large contexts into smaller ones.
• Use context only when necessary; for local state, stick to component state.

5. FAQ