Learn React Hooks

Trigger effect only on mount

If we want to replicate the behavior of only adding a componentDidMount life cycle method, without triggering when the props change, we can do this by passing an empty array as the second argument to the useEffect Hook:

    useEffect(() => {        document.title = title    }, [])

Passing an empty array means that our effect function will only trigger once when the component mounts, and it will not trigger when props change. However, instead of thinking about the mounting of components, with Hooks, we should think about the dependencies of effects. In this case, the effect does not have any dependencies, which means it will only trigger once. If an effect has dependencies specified, it will trigger again when any of the dependencies ...