There are the following approaches to update nested state properties in ReactJS:
- Approach 1: We can create a dummy object to perform operations on it (update properties that we want) then replace the component’s state with the updated object.
- Approach 2: We can pass the old nested object using the spread operator and then override the particular properties of the nested object.
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.
Approach 1: App.js
Javascript
import React, { Component } from "react" ; class App extends Component { // Nested object state = { name: 'kapil' , address: { colony: 'vaishnav nagar' , city: 'Jaipur' , state: 'Rajasthan' } }; handleUpdate = () => { // Creating a dummy object using spread operator var address = { ... this .state.address } // Updating the city address.city = 'Kota' ; this .setState({ address }) } render() { return ( <div style={{ margin: 200 }}> <h1>{ this .state.name}</h1> <h1>{ this .state.address.colony} { "," } { this .state.address.city}{ ", " } { this .state.address.state}</h1> <button onClick={ this .handleUpdate} >UpdateCity </button> </div> ); } } export default App; |
Approach 2: App.js
Javascript
import React, { Component } from "react" ; class App extends Component { // Nested object state = { name: 'kapil' , address: { colony: 'vaishnav nagar' , city: 'Jaipur' , state: 'Rajasthan' } }; handleUpdate = () => { // Overriding the city property of address object this .setState({ address: { ... this .state.address, city: "kota" } }) } render() { return ( <div style={{ margin: 200 }}> <h1>{ this .state.name}</h1> <h1>{ this .state.address.colony} { "," } { this .state.address.city}{ ", " } { this .state.address.state}</h1> <button onClick={ this .handleUpdate} >UpdateCity </button> </div> ); } } export default App; |
Step to Run Application: Run the application using the following command from the root directory of the project:
npm start
Output: