When should a constructor react?
Similarly, it is asked, why do you need a constructor in react?
The constructor is a method that's automatically called during the creation of an object from a class. Simply put, the constructor aids in constructing things. In React, the constructor is no different. It can be used to bind event handlers to the component and/or initializing the local state of the component.
Also Know, when should I use componentWillUnmount? componentWillUnmount is the last function to be called immediately before the component is removed from the DOM. It is generally used to perform clean-up for any DOM-elements or timers created in componentWillMount . At a picnic, componentWillUnmount corresponds to just before you pick up your picnic blanket.
Also Know, which method updates the state of the constructor?
Updating component states state . The only place you should directly write to this. state is the component's constructor method. Use the setState() method everywhere else, doing so will accept an object that will eventually be merged into the component's existing state.
When should I use componentDidUpdate?
The componentDidUpdate is particularly useful when an operation needs to happen after the DOM is updated and the update queue is emptied. It's probably most useful on complex renders and state or DOM changes or when you need something to be the absolutely last thing to be executed.