When might you use React.PureComponent?

ReactJS - Quiz(MCQ)

when you do not want your component to have state

when you have sibling components that need to be compared

when you want a default implementation of shouldComponentUpdate()

when you do not want your component to have props

Correct Answer : when you want a default implementation of shouldComponentUpdate()

Recent Updates in React.JS

Q .

What do you need to change about this code to get it to run?

class clock extends React.Component {
  render() {
    return <h1>Look at the time: {this.props.time}</h1>;
  }
}

Remove this

Capitalize clock

Remove the render method

Add quotes around the return value

Correct Answer : Capitalize clock

Q .

Which Hook could be used to update the document's title?

useEffect(function updateTitle() { document.title = name + ' ' + lastname; });

useEffect(() => { title = name + ' ' + lastname; });

useEffect(function updateTitle() { name + ' ' + lastname; });

useEffect(function updateTitle() { title = name + ' ' + lastname; });

Correct Answer :

useEffect(function updateTitle() { document.title = name + ' ' + lastname; });