Angular Web Framework Components & Templates 3

Question 1

Which Angular template syntax creates a local template reference variable for a DOM element?

Accepted Answer

#refName

Answer

The hash (#) prefix in a template creates a local reference variable that can be used elsewhere in the same template.

Question 2

What does the `async` pipe do when used in a template with an Observable?

Accepted Answer

Subscribes and automatically unsubscribes, rendering the latest value

Answer

The async pipe manages the subscription lifecycle and pushes each emitted value into the template, unsubscribing on destroy.

Question 3

In an Angular template, what does `(click)="handler($event)"` demonstrate?

Accepted Answer

Event binding with $event payload

Answer

Parentheses denote event binding, and $event is the DOM event object passed to the handler function.

Question 4

Which directive would you use to repeat a block of HTML for each item in an array in Angular 17+ with the new built-in control flow?

Accepted Answer

@for

Answer

Angular 17 introduced the @for built-in control flow block as the modern replacement for the *ngFor structural directive.

Question 5

What is the role of `trackBy` in an *ngFor directive?

Accepted Answer

Helps Angular identify items to minimize DOM re-renders

Answer

trackBy provides a unique identifier per item so Angular can reuse existing DOM nodes instead of destroying and recreating them.

Angular Web Framework Practice Test