How do you memoize a component?

ReactJS - Interview Questions

There are memoize libraries available which can be used on function components.

For example moize library can memoize the component in another component.

import moize from 'moize'
import Component from './components/Component' // this module exports a non-memoized component

const MemoizedFoo = moize.react(Component)

const Consumer = () => {
  <div>
    {'I will memoize the following entry:'}
    <MemoizedFoo/>
  </div>
}

Update : Since React v16.6.0, we have a React.memo. It provides a higher order component which memoizes component unless the props change. To use it, simply wrap the component using React.memo before you use it.

  const MemoComponent = React.memo(function MemoComponent(props) {
    /* render using props */
  });
  OR
  export default React.memo(MyFunctionComponent);