What is the purpose of callback function as an argument of setState()?

The callback function is invoked when setState finished and the component gets rendered. Since setState() is asynchronous the callback function is used for any post action.

Note: It is recommended to use lifecycle method rather than this callback function.

setState({ name: 'John' }, () => console.log('The name has updated and component re-rendered'));

Made in India with ❤️ by Rajesh Kumar Yadav