The defaultProps is a React component property that allows you to set default values for the props argument. If the prop property is passed, it will be changed. The defaultProps can be defined as a property on the component class itself, to set the default props for the class.
Creating React Application:
Step 1: Create a React application using the following command:
npx create-react-app foldername
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.
Creating defaultProps in class-based component: Now write down the following code in the App.js file. Here, App is our default component where we have written our code using a class-based component.
App.js
import React, { Component } from 'react'; Â Â class App extends Component { Â Â render() { Â Â Â Â return ( Â Â Â Â Â Â <div > Â Â Â Â Â Â Â Â <Person name="kapil" eyeColor="blue" age="23"></Person> Â Â Â Â Â Â Â Â <Person name="Sachin" eyeColor="blue" ></Person> Â Â Â Â Â Â Â Â <Person name="Nikhil" age="23"></Person> Â Â Â Â Â Â Â Â <Person eyeColor="green" age="23"></Person> Â Â Â Â Â Â </div> Â Â Â Â ); Â Â } } Â Â class Person extends Component { Â Â render() { Â Â Â Â return ( Â Â Â Â Â Â <div> Â Â Â Â Â Â Â Â <p> Name: {this.props.name} </p> Â Â Â Â Â Â Â Â <p>EyeColor: {this.props.eyeColor}</p> Â Â Â Â Â Â Â Â <p>Age : {this.props.age} </p> Â Â Â Â Â Â </div> Â Â Â Â ) Â Â } } Â Â Person.defaultProps = { Â Â name: "Rahul", Â Â eyeColor: "deepblue", Â Â age: "45"} Â Â 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:
Creating defaultProps in Functional Component: Now write down the following code in the App.js file. Here, App is our default component where we have written our code using a functional component.
App.js
import React from 'react'; Â Â function App(props) { Â Â return ( Â Â Â Â <div > Â Â Â Â Â Â <Person name="kapil" eyeColor="blue" age="23"></Person> Â Â Â Â Â Â <Person name="Sachin" eyeColor="blue" ></Person> Â Â Â Â Â Â <Person name="Nikhil" age="23"></Person> Â Â Â Â Â Â <Person eyeColor="green" age="23"></Person> Â Â Â Â </div> Â Â ); } Â Â function Person(props) { Â Â return ( Â Â Â Â <div> Â Â Â Â Â Â <p> Name: {props.name} </p> Â Â Â Â Â Â <p>EyeColor: {props.eyeColor}</p> Â Â Â Â Â Â <p>Age : {props.age} </p> Â Â Â Â Â Â <hr></hr> Â Â Â Â </div> Â Â ) } Â Â Person.defaultProps = { Â Â name: "Rahul", Â Â eyeColor: "deepblue", Â Â age: "45"} Â Â 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:
