[Solved] You have this Angular component:export class DataComponent implements OnDestroy { subscription = this.dataService.getData().subscribe();... } }What is the problem with this code? | Angular

Angular - Lifecycle Hooks

You have this Angular component:

export class DataComponent implements OnDestroy {
  subscription = this.dataService.getData().subscribe();

  ngOnDestroy() {
    this.subscription.unsubscribe;
  }
}

What is the problem with this code?

AThe unsubscribe method is not called correctly

BThe subscription is never created

CngOnDestroy is missing the return type

DThere is no problem; code works fine

Step-by-Step Solution

Solution:

Step 1: Check how unsubscribe is used
The code uses this.subscription.unsubscribe; without parentheses, so the method is not actually called.
Step 2: Correct usage of unsubscribe
It should be this.subscription.unsubscribe(); to properly stop the subscription and avoid memory leaks.
Final Answer:
The unsubscribe method is not called correctly -> Option A
Quick Check:
Call unsubscribe() with parentheses [OK]

Quick Trick: Always call unsubscribe() as a function [OK]

Common Mistakes:

Forgetting parentheses on unsubscribe
Assuming unsubscribe is a property
Ignoring ngOnDestroy lifecycle

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More Angular Quizzes

You have this Angular component:

Step 1: Check how unsubscribe is used

Step 2: Correct usage of unsubscribe

Final Answer:

Quick Check:

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