Angular Online Test - MCQ Questions

Dive into our Angular Online Test, specifically created to evaluate your expertise and knowledge of Angular, a robust platform for building mobile and desktop web applications. This test features 25 carefully selected multiple-choice questions (MCQs) encompassing various Angular-specific topics, including modules, components, services, routing, and data binding.

1. Which CLI command is used to create a new Angular component?

a) ng generate component

b) ng create component

c) ng new component

d) ng component create

2. What is the purpose of the ngOnInit lifecycle hook in Angular components?

a) To handle any additional initialization tasks

b) To set up new data-binding properties

c) To declare dependencies

d) To send HTTP requests

3. Which decorator is used to define a service in Angular?

a) @Injectable()

b) @Component()

c) @Directive()

d) @NgModule()

4. How do you bind to an event in Angular?

<button (click)="doSomething()">
   Click me!
</button>

a) [click]="doSomething()"

b) (event)="doSomething()"

c) (click)="doSomething()"

d) {{click}}="doSomething()"

5. Which Angular feature allows you to format displayed values?

a) Services

b) Directives

c) Pipes

d) Modules

6. What does the following code snippet define in an Angular application?

@NgModule({
    imports: [BrowserModule],
    declarations: [AppComponent],
    bootstrap: [AppComponent]
    })
export class AppModule { }

a) A component

b) A module

c) A service

d) A directive

7. How do you create a two-way data binding to a form input in Angular?

<input [(ngModel)]="user.name">

a) [ngModel]="user.name"

b) (ngModel)="user.name"

c) {{ngModel}}="user.name"

d) [(ngModel)]="user.name"

8. Which Angular directive is used to conditionally add or remove an element from the DOM?

a) *ngIf

b) *ngFor

c) *ngSwitch

d) *ngModel

9. What is the correct syntax for defining an input property in an Angular component?

a) @Input() prop: string;

b) @Output() prop: string;

c) @Prop() input: string;

d) @Receive() prop: string;

10. Which of the following is true about Angular services?

a) They are only accessible within the component they are declared in.

b) They must be provided in the component's providers array.

c) They can be shared across components.

d) They cannot be injected into other services.

11. What is the use of the async pipe in Angular?

a) It executes functions in a web worker.

b) It unsubscribes from Observables automatically.

c) It manages promise resolution automatically.

d) Both b) and c) are correct.

12. What will the following Angular template syntax display?

<p>{{ 1 + 1 }}</p>

a) 2

b) 1 + 1

c) Nothing

d) Error

13. How do you capture a reference to a DOM element in Angular?

a) Using the @ViewChild decorator

b) Using the @ContentChild decorator

c) Using the @ElementRef decorator

d) Using the @CaptureRef decorator

14. Which method in the HTTP module is used to send a GET request in Angular?

a) get()

b) post()

c) send()

d) query()

15. What does the RouterModule in Angular help with?

a) Localization

b) Navigation

c) Validation

d) Optimization

16. How can you ensure a service remains singleton in Angular?

a) Declare it in the AppModule only.

b) Use the @Singleton decorator.

c) Provide it in the component's providers array.

d) Use the providedIn: 'root' option in the @Injectable() decorator.

17. What is the purpose of Angular's NgZone service?

a) To manage the execution outside Angular's zone to optimize performance.

b) To keep track of the loaded modules.

c) To enhance the synchronization between different components.

d) To intercept HTTP requests and responses.

18. Which decorator is used to listen to global events, like window resize, in Angular?

a) @HostListener()

b) @GlobalListener()

c) @WindowListener()

d) @DocumentListener()

19. What is the use of the trackBy function in the *ngFor directive?

a) To track items by a unique identifier for performance optimization.

b) To hide elements in the DOM.

c) To sort data in a list.

d) To track errors in the application.

20. What does the following code snippet accomplish in an Angular component?

@Input() set config(value: Config) {
    console.log('Configuration set:', value);
}

a) It creates a setter for an input property that logs the new value.

b) It declares a new variable in the component.

c) It configures a service.

d) It sends an HTTP GET request.

21. How do you apply multiple structural directives to one element in Angular?

a) It's not possible; only one structural directive can be applied per element.

b) Use multiple attributes on the same element.

c) Combine directives in a single attribute.

d) Nest multiple elements, each with one directive.

22. What is the main benefit of using the OnPush change detection strategy in Angular components?

a) It checks for changes only when new references are passed to inputs.

b) It forces a component to re-render every time data changes.

c) It disables change detection for performance gains.

d) It provides a deep check of every component.

23. What is the role of @Output() in Angular?

a) It marks a property as an input property.

b) It allows a component to expose an EventEmitter to emit events.

c) It declares a method as an event handler.

d) It marks a function to be run on server side.

24. Which of the following is a valid method to handle form submission in Angular?

a) Subscribe to the ngSubmit event.

b) Bind the submit event and call a method.

c) Use the formControl directive on the submit button.

d) All of the above.

25. What is the advantage of using lazy loading modules in Angular?

a) It increases the initial load time of the application.

b) It decreases the overall size of the application.

c) It loads features as they are needed, improving the startup time.

d) It synchronizes module loading.