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KenjiGoh
KenjiGoh

Posted on • Updated on

React UseContext is Simple

Why use UseContext?

React useContext hook is used to create global data that can be accessed throughout the component hierarchy without the need to keep passing the props down manually to each component level.

This process of manually passing props down each level of child components (even though some child level does not need the data) to eventually reach the target child component is called Prop Drilling. Using useContext can help resolve this tedious process of Prop Drilling!

Simplified code snippets

In Parent component or App.js, we just need to create & export the context, literally by using the createContext hooks! Simply use these few lines of code:

// in App.js
import {createContext} from 'react';
export const contextToPassDown = createContext();
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Then wrap the context Provider over the child components you wish to provide the context

<contextToPassDown.Provider value={dataToPassDown}>
   <ChildComponent />
</contextToPassDown.Provider>
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Then in any Child components that are wrapped by the tag, we just need to use the useContext hooks!

// in ChildComponent.js
import {useContext} from 'react';
import {contextToPassDown} from App.js;

const ChildComponent=()=>{
  const contextToUse = useContext(contextToPassDown);

  return (<div> {contextToUse.username} </div>);
}

export default ChildComponent;
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The use cases for useContext are usually:

  1. To Pass down logged-in user info to authorized components
  2. For 'light' or 'dark' theme

You may practice using this link to: codesandbox

Top comments (8)

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sgarciadev profile image
Sergei Garcia

Congrats on your second post! But I agree with @code913 , this is a pretty low quality post. Some tips for your next one:

  • Always assume your reader has no idea what you are talking about. Nowhere in your article did you explain what React Context was, what problem it solves, or why you should use it
  • Consider annotating your code examples with more comments.
  • Consider a longer article length. Too short and it comes off as low quality and something that could have been a comment. Too long and people won't find it interesting.
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kenji_goh profile image
KenjiGoh

Thanks for all the tips! I oversimplified the post!:)

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lalami profile image
Salah Eddine Lalami

@ IDURAR , we use react context api for all UI parts , and we keep our data layer inside redux .

Here Article about : 🚀 Mastering Advanced Complex React useContext with useReducer ⭐ (Redux like Style) ⭐ : dev.to/idurar/mastering-advanced-c...


Mastering Advanced Complex React useContext with useReducer (Redux like Style)

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markewers profile image
Mark Ewers

I found this helpful. Thanks for posting.

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wkrueger profile image
wkrueger

Never use condescending language. It is toxic.

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kenji_goh profile image
KenjiGoh

Thanks for the feedback! did not intend to be condescending! :)

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kenji_goh profile image
KenjiGoh

thanks for the feedback!

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D-Javohir

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