[Solved] What is the likely performance impact of using trackBy in an *ngFor directive? — Ans: Improves performance by reducing DOM manipulations | Angular

Angular - Performance Optimization

What is the likely performance impact of using trackBy in an *ngFor directive?

AImproves performance by reducing DOM manipulations

BSlows down rendering by adding extra checks

CHas no effect on performance

DCauses Angular to reload the entire list every time

Step-by-Step Solution

Solution:

Step 1: Understand trackBy purpose
trackBy helps Angular identify items uniquely to avoid unnecessary DOM updates.
Step 2: Connect trackBy with performance
By reducing DOM changes, trackBy improves rendering speed and efficiency.
Final Answer:
Improves performance by reducing DOM manipulations -> Option A
Quick Check:
trackBy reduces DOM updates = better performance [OK]

Quick Trick: Use trackBy to optimize *ngFor rendering [OK]

Common Mistakes:

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What is the likely performance impact of using trackBy in an *ngFor directive?