[Solved] Why is it important to implement ngOnDestroy in components that subscribe to observables? — Ans: To prevent memory leaks by unsubscribing when component is destroyed | Angular

Angular - Lifecycle Hooks

Why is it important to implement ngOnDestroy in components that subscribe to observables?

ATo automatically refresh data when component is destroyed

BTo prevent memory leaks by unsubscribing when component is destroyed

CTo delay component destruction until subscriptions complete

DTo restart subscriptions after component destruction

Step-by-Step Solution

Solution:

Step 1: Understand subscription lifecycle
Subscriptions keep resources active; if not unsubscribed, they cause memory leaks.
Step 2: Role of ngOnDestroy
ngOnDestroy is used to unsubscribe from observables to free resources when component is destroyed.
Final Answer:
To prevent memory leaks by unsubscribing when component is destroyed -> Option B
Quick Check:
Unsubscribe in ngOnDestroy to avoid leaks [OK]

Quick Trick: Unsubscribe in ngOnDestroy to prevent leaks [OK]

Common Mistakes:

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Why is it important to implement ngOnDestroy in components that subscribe to observables?