Angular Web Framework Angular Advanced Practice 5

Question 1

In Angular, what is the difference between `ViewChild` and `ContentChild`?

Accepted Answer

ViewChild queries the host component's template; ContentChild queries content projected via ng-content

Answer

ViewChild accesses elements/components defined in the component's own template, while ContentChild accesses elements projected into the component from the outside via <ng-content>.

Question 2

Which Angular feature would you use to share state between sibling components without a shared parent component or a service?

Accepted Answer

A shared singleton service with a BehaviorSubject or Signal

Answer

A singleton service holding a BehaviorSubject or Signal acts as a shared state store that any component can inject, read, and write regardless of their position in the component tree.

Question 3

What problem does the `NgZone.runOutsideAngular()` method solve?

Accepted Answer

It runs code without triggering Angular's change detection, avoiding unnecessary UI checks for frequent events like scroll or mousemove

Answer

Running high-frequency event handlers outside Angular's zone stops them from triggering change detection on every event, significantly improving performance.

Question 4

In Angular's dependency injection, what does the `@Self()` decorator do?

Accepted Answer

Limits DI resolution to the component's own injector only, not parent injectors

Answer

@Self() tells Angular to only look for the dependency in the current component or directive's own injector and throw if not found there.

Question 5

What is the purpose of `ng-template` combined with `*ngTemplateOutlet` in Angular?

Accepted Answer

To define reusable template fragments that can be rendered conditionally or in multiple locations

Answer

ng-template defines an inert template block, and ngTemplateOutlet renders it at a chosen location with optional context variables, enabling powerful template reuse patterns.

Angular Web Framework Practice Test

Angular Web Framework Practice Test

Angular Web Framework Angular Advanced Practice 5