“‘X’ is not defined react/jsx-no-undef” is a common error that shows up in many ways. What is the cause of it and how to fix it? Read on this article to find the best answer.

How Does The Error “‘X’ is not defined react/jsx-no-undef” Happen?

While running your program, you easily get the following error:

‘X’ is not defined react/jsx-no-undef

When you try to utilize a module that you haven’t imported, this error often happens. Or sometimes you have imported it twice, this is also a reason of the problem “‘X’ is not defined react/jsx-no-undef”.

How To Solve The Error “‘X’ is not defined react/jsx-no-undef”?

Approach 1: Import that module

The simplest solution for you to resolve the error “‘X’ is not defined react/jsx-no-undef” is that you have to import that module and then your problem will be fixed. Look at the following example:

import {useState} from 'react';
const App = () => {
  const [count, setCount] = useState(0);

In the above example, we are attempting to use useState without importing it, we get this error. But when we imported it, the error will completely disappear.

Approach 2: Don’t import one module twice

Sometimes, if you import one module twice, it also causes the error “‘X’ is not defined react/jsx-no-undef“. So, in this case you have to remove or rename the extra import as shown below to solve your problem:

import Header from './Components/Common/Header';
import Hedaer from './Header';

Approach 3: Make sure your variables are specified

Another solution is that you have to make sure your variables are specified.

For example, you can write as the following to import the Map variable from the Map module.

import Map from "./Map";

Approach 4: Export a component correctly

Occasionally, your export is the problem. You should understand the various export types and how to import them if you export a custom component. If you are attempting to export default, let’s do as the following:

export default MyCustomComponent;

Next, you must import the default export as shown below:

import MyCustomComponent from './myCustomComponent';

Additionally, if you do not use default exports similar to const or another.

export const MyCustomComponent = () => { .... }

After that, let’s import it between curly brackets similar to this:

import { MyCustomComponent } from './myCustomComponent';

After finishing these steps, your error completely disappear.

Conclusion

The techniques presented above are simple methods to the issue “‘X’ is not defined react/jsx-no-undef“. We believe you can easily resolve your problem with these methods. If you have any further concerns, you can leave your suggestions and ideas in the comments section. Thank you for your reading.

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