React.js library is all about splitting the app into several components. Each Component has its own lifecycle. React provides us some in-built methods that we can override at particular stages in the life-cycle of the component.
In this article, we will know how to use checked or defaultChecked attribute in checkbox input in React.js.
The checked attribute can be used with a checkbox or RadioButton element.Â
Creating React Application And Installing Module:
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Step 1: Create a React application using the following command.
npx create-react-app foldername
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Step 2: After creating your project folder i.e. foldername, move to it using the following command.
cd foldername
Project Structure: It will look like the following.
Example 1: Now write down the following code in the App.js file. Here, App is our default component where we have written our code.
App.js
import React from 'react';   // Defining our App Component const App = () => {     // Returning our JSX code   return <>     <div>       <h1>neveropen</h1>         Input: <input type='checkbox' checked={true} />     </div>   </>; }   // Exporting your Default App Component export default App |
Step to Run Application: Run the application using the following command from the root directory of the project:
npm start
Output: Now open your browser and go to http://localhost:3000/, you will see the following output:
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Example 2: Now write down the following code in the App.js file. Here, App is our default component where we have written our code.
Javascript
import React from 'react';   // Defining our App Component const App = () => {     // Returning our JSX code   return <>     <div>       <h1>neveropen</h1>         Input: <input type='radio' checked={true} />     </div>   </>; }   // Exporting your Default App Component export default App |
Step to Run Application: Run the application using the following command from the root directory of the project:
npm start
Output: Now open your browser and go to http://localhost:3000/, you will see the following output:
Reference:https://reactjs.org/docs/dom-elements.html#checked
