React is an independent as well as wide open-source front-end JavaScript toolkit for Creative UI components-based user interfaces. It is sometimes known as React.js or ReactJS. It is kept up-to-date by Meta (formerly known as Facebook) and a group of independent programmers and businesses. “‘React’ must be in scope when using JSX react/react-in-jsx-scope” is a common error. This article will focus on some solutions to resolve it. Keep reading to explore them.

When Does The Error “‘React’ must be in scope when using JSX react/react-in-jsx-scope” Happen?

You may encounter the following error when you run your program:

'React' must be in scope when using JSX react/react-in-jsx-scope

Your program will be executed when constructing your component because JSX is nothing more than syntactic sugar for the createElement function. The problem is that you have never imported React into the context of your file. What will take place?

Exactly, you will encounter the problem “‘React’ must be in scope when using JSX react/react-in-jsx-scope”.

React.createElement would crash if it wasn’t imported at the beginning of the file because React would otherwise be undefined.

What is scope in React?

To obtain details about the client’s application, React Scope makes use of the React Developer Tools. The rendering of a DOM tree visualization is then done using this data. To view the name, status, and properties of each component, the user only needs to hover their cursor over the tree’s nodes.

How To Solve The Error “‘React’ must be in scope when using JSX react/react-in-jsx-scope”

Option 1: Import in this way

Perhaps you are importing React with the incorrect spelling, which is why this problem happens. Now, you simply import React in this way to solve the error “‘React’ must be in scope when using JSX react/react-in-jsx-scope”.

import React, { Component } from 'react';

After doing that, your error will be completely resolved.

Option 2: Add the following option to.eslintrc.js or.eslintrc.json

Another solution we suggest you is ignoring your errors. To disregard these errors, add the following option to.eslintrc.js or.eslintrc.json:

rules: { 
   // suppress errors for missing 'import React' in files 
   "react/react-in-jsx-scope": "off", 
   // allow jsx syntax in js files (for next.js project) 
   "react/jsx-filename-extension": [1, { "extensions": [".js", ".jsx"] }], 
   //should add ".ts" if typescript project
 }

This solution also helps you understand more about ESLint.

ESLint is a tool for finding patterns in ECMAScript/JavaScript code and reporting them, with the aim of improving consistency and reducing problems. With a few exceptions, it resembles JSLint and JSHint in many ways:

• Espree is used by ESLint to parse JavaScript.
• ESLint analyzes code patterns using an AST.
• Every single rule in ESLint is a plugin, and more rules can be added at any time.

Option 3: Install the react-require babel plugin

Install the react-require babel plugin if you’d like to automatically include import React from’react’ for all scripts that use jsx syntax:

npm install babel-plugin-react-require --save-dev

In the.babelrc file, add react-require. Due to the fact that it uses the syntax of ES2015 modules to import React into scope, this plugin should be defined before transform-es2015-modules-commonjs.

{
"plugins": [
"react-require"
]
}

Conclusion

JSX is the name given to JavaScript XML. It is essentially a syntactic JavaScript extension. It enables us to write HTML directly in React (inside the code of JavaScript). If you are perplexed by the error “‘React’ must be in scope when using JSX react/react-in-jsx-scope“, the solutions presented here are the most effective. Even if you still need assistance or have fundamental Mongodb questions, there is a large community to which you can turn, and everyone is usually eager to assist. Finally, we wish all of our readers a fantastic day full of new ideas. Thank you for reading!

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