We can pass a function setting the state from the parent to the child component as a prop.
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.
Filename: App.js
Javascript
import React, { Component } from "react" ; class App extends Component { state = { text: 'click me' } // Function to update state handleUpdate = (newtext) => { this .setState({ text: newtext }) } render() { return ( <div> <Child text={ this .state.text} // Passing a function to child updateState={ this .handleUpdate}> </Child> </div> ); } } class Child extends Component { render() { return ( <button // Using parent props to update parent state onClick={() => this .props .updateState( 'parent state changed' )}> { this .props.text} </button> ) } } export default App; |
Step to Run Application: Run the application using the following command from the root directory of the project:
npm start
Output: You will see the following button on the screen:
After clicking on the button, the following will be the output: