Chapter quiz · Components Deep Dive

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8 questions on Components Deep Dive. Pass 70% to clear the chapter.

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Quiz

Components Deep Dive — Chapter Quiz

Eight questions on inputs, outputs, projection, lifecycle, and change detection.

0/ 9

Question 1
1
What does input.required<string>() return?
AA plain string propertyBA signal-backed required inputCAn EventEmitterDAn observable
input.required<T>() returns a Signal<T>. The parent must bind a value or the compiler flags a missing-input error.
Question 2
2
How does a child component declare a custom event the parent can listen to?
Asaved = input<User>()Bsaved = output<User>()Csaved = signal<User>()Dsaved = inject(EventEmitter)
output<T>() declares an outgoing event. Emit with saved.emit(value); the parent listens with (saved)="...".
Question 3
3
What does <ng-content> do?
AProjects content from the parent into the childBRenders a router outletCIncludes another component by selectorDOutputs HTML from a signal
<ng-content> is the projection slot. Whatever the parent writes between the child's tags shows up where <ng-content> is.
Question 4
4
Which ChangeDetectionStrategy re-checks only on input/signal changes?
ADefaultBOnPushCManualDDetached
OnPush skips re-checking unless an input reference changes or a signal it reads updates. Default re-checks on every event.
Question 5
5
Which lifecycle hook runs after Angular initialises a component's inputs?
AngAfterViewInitBngOnInitCngOnDestroyDngDoCheck
ngOnInit runs once after the first ngOnChanges — inputs are set, but the view hasn't been queried yet.
Question 6
6
viewChild() returns a signal you can read in the template or in effects.
TTrueFFalse
The signal-based viewChild() (and viewChildren()) replaces the older @ViewChild decorator and integrates with signals.
Question 7
7
The @Component({ encapsulation: ___ }) value that uses Shadow DOM is ShadowDom.
ViewEncapsulation.ShadowDom puts the component template inside a shadow root. Default is Emulated, which scopes CSS via attribute selectors.
Question 8
8
Which of these are valid Angular lifecycle hooks?
Select all that apply.
AngOnInitBngAfterViewInitCngBeforeRenderDngOnDestroyEngOnChanges
ngBeforeRender doesn't exist. The closest equivalent is the newer afterNextRender / afterRender callbacks.