How componentWillUnmount works?

Question

Accepted Answer

componentWillUnmount is a lifecycle method in React that is called right before a component is unmounted and destroyed.

componentWillUnmount is used to perform any necessary cleanup tasks before a component is removed from the DOM.
It is commonly used to cancel any pending network requests, remove event listeners, or clear timers or intervals.
The method is called automatically by React when a component is about to be unmounted.
It is important to clean up any resources or subscriptions to prevent memory leaks or unexpected behavior.
Here is an example of how componentWillUnmount can be used to remove an event listener: componentWillUnmount() { window.removeEventListener('resize', this.handleResize); }

Accepted Answer

componentWillUnmount() is a lifecycle method in React that is called just before a component is unmounted and removed from the DOM. This method is useful for cleaning up any resources that the component has acquired during its lifecycle, such as event listeners or timers, to avoid memory leaks.

Here's how componentWillUnmount() works in React:

When a component is about to be removed from the DOM, React calls componentWillUnmount() on the component.
Inside the componentWillUnmount() method, you can clean up any resources that the component has acquired during its lifecycle, such as event listeners or timers. This is important to avoid memory leaks and ensure that the component is fully unmounted.
After componentWillUnmount() is called, React will remove the component from the DOM and any references to the component will be removed from memory.

How componentWillUnmount works?

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