30-seconds-of-code/snippets/useComponentDidMount.md

title, tags

title	tags
useComponentDidMount	hooks,effect,beginner

Executes a callback immediately after a component is mounted.

• Use useEffect() with an empty array as the second argument to execute the provided callback only once when the component is mounted.
• Behaves like the componentDidMount() lifecycle method of class components.

const useComponentDidMount = onMountHandler => {
  React.useEffect(() => {
    onMountHandler();
  }, []);
};

const Mounter = () => {
  useComponentDidMount(() => console.log('Component did mount'));

  return <div>Check the console!</div>;
};

ReactDOM.render(<Mounter />, document.getElementById('root'));