Angular Web Framework Angular Advanced Practice 4

Question 1

What Angular feature allows you to write `@if`, `@for`, and `@switch` directly in templates without importing `NgIf`, `NgFor`, or `NgSwitch` directives?

Accepted Answer

Built-in control flow (Angular 17+)

Answer

Angular 17 introduced built-in control flow syntax (@if, @for, @switch) that is compiled directly by the framework without needing CommonModule or directive imports.

Question 2

What is the primary benefit of using `inject()` function instead of constructor-based injection in Angular services and components?

Accepted Answer

It allows injection outside of class constructors, such as in functions and field initializers

Answer

The inject() function can be called in an injection context (constructor, field initializer, factory function) and enables functional patterns without needing class constructors.

Question 3

In Angular's HttpClient, which operator or mechanism should you use to retry a failed HTTP request up to 3 times with a delay between retries?

Accepted Answer

retry(3) from RxJS

Answer

The RxJS retry(3) operator resubscribes to the source Observable (the HTTP call) up to 3 times on error, and retry({ count: 3, delay: 1000 }) adds a delay.

Question 4

Which Angular Signal API allows you to create a derived reactive value that recomputes automatically when its dependencies change?

Accepted Answer

computed()

Answer

computed() creates a read-only Signal whose value is lazily recalculated whenever any of the Signals it reads inside its function change.

Question 5

What does the `resolveComponentFactory` approach get replaced by in modern Angular when dynamically creating components?

Accepted Answer

ViewContainerRef.createComponent() with a component class directly

Answer

Since Angular 13, ViewContainerRef.createComponent(MyComponent) accepts the component class directly without needing ComponentFactoryResolver or resolveComponentFactory.

Angular Web Framework Practice Test

Angular Web Framework Practice Test

Angular Web Framework Angular Advanced Practice 4