Angular Lifecycle Hooks Explained: From Creation to Destruction

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Angular provides a set of lifecycle hook methods that are invoked on components and directives at key moments such as creation, change detection, and destruction. Hooks like ngOnInit, ngOnChanges, and ngOnDestroy allow developers to run logic at precise points in a component's life. While implementing the corresponding interfaces such as OnInit or OnDestroy is optional, it is recommended for better type safety. Key distinctions exist between hooks — for example, the constructor should only be used for dependency injection, while ngOnInit is the right place for input-dependent initialization logic. Cleanup hooks like ngOnDestroy are essential for preventing memory leaks by clearing timers, subscriptions, and event listeners.

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