By Vishal Basumatary in javascript — Mar 24, 2023

useSelector for choose a state

If you are using React and Redux in your application, you may have come across the need to get the state from your Redux store. One way to do this is by using the useSelector hook provided by the React-Redux library. This hook allows you to extract data from the Redux store state.

How to use `useSelector`

First, you need to import both the useSelector hook and the Redux store into your component:


import { useSelector } from 'react-redux';
import store from '../store';

You can then use the useSelector hook to select the parts of the state you need. For example, if you have a counter slice of your store state, you can use it like this:


const counter = useSelector(state => state.counter);

The state argument passed to the useSelector hook is the current Redux state. You can then return the part of the state you need.

Multiple selectors

You can also use multiple selectors with the useSelector hook:


const { counter, user } = useSelector(state => ({
  counter: state.counter,
  user: state.user
}));

This way, you can extract multiple parts of the state in a single call.

Memoization

The useSelector hook uses memoization to optimize performance. This means that it only rerenders your component when the selected part of the state changes. This can greatly improve the performance of your application.

Conclusion

The useSelector hook is an easy and efficient way to extract data from your Redux store state. It allows you to select the parts of the state you need and only rerenders your component when needed. Use it to simplify your code and improve your application's performance.