[Solved] Identify the issue in this Angular component's ngOnDestroy method:export class CleanupComponent implements OnDestroy { private timerId: any; ngOnDestroy() { clearInterval(timerId); } } | Angular

Angular - Lifecycle Hooks

Identify the issue in this Angular component's ngOnDestroy method:

export class CleanupComponent implements OnDestroy {
  private timerId: any;

  ngOnDestroy() {
    clearInterval(timerId);
  }
}

AclearInterval should be replaced with clearTimeout

BThe variable <code>timerId</code> is not referenced with <code>this</code> inside ngOnDestroy

CngOnDestroy should return a value

DThe component should implement OnInit instead of OnDestroy

Step-by-Step Solution

Solution:

Step 1: Check variable usage
Inside class methods, instance variables must be accessed with this.
Step 2: Analyze the code
The code calls clearInterval(timerId) but timerId is not defined locally; it should be this.timerId.
Step 3: Correct usage
Use clearInterval(this.timerId) to properly clear the interval.
Final Answer:
The variable timerId is not referenced with this inside ngOnDestroy -> Option B
Quick Check:
Use this.timerId to access instance variable [OK]

Quick Trick: Always prefix instance variables with this. inside methods [OK]

Common Mistakes:

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