When creating a Route Resolver, it must implement the _____ interface.
- Resolve interface
- ResolveInterceptor
- Resolveable
- RouterResolver
When creating a Route Resolver, it must implement the Resolve interface. The Resolve interface defines a method to retrieve data for a route before it is activated.
The router-outlet directive acts as a _____ where the routed component is displayed.
- Container
- Directive
- Placeholder
- Router hub
The router-outlet directive acts as a placeholder where the routed component is displayed in Angular routing.
In Angular, using the _____ pipe can automatically handle subscription and unsubscription, preventing memory leaks.
- Async
- Observer
- Promise
- Subscribe
In Angular, using the Async pipe can automatically handle subscription and unsubscription, preventing memory leaks by managing the observable's lifecycle for you.
To create a custom directive that modifies the structure of the DOM, you would use a _____ directive.
- attribute
- component
- service
- structural
To modify the structure of the DOM, you would use a structural directive in Angular, such as ngFor or ngIf.
You need to implement a feature where clicking on a user's name in a list navigates to a detailed user profile page. The user ID needs to be passed in the URL. How would you implement this using Angular's router?
- Create a custom directive to handle the navigation and pass the user ID.
- Define a route with a parameter like /user/:userId and access the userId using ActivatedRoute.
- Store the user ID in a global service and retrieve it when navigating to the user profile page.
- Use a query parameter to pass the user ID in the URL and retrieve it using the QueryParams.
To navigate to a detailed user profile page with the user ID in the URL, you should define a route with a parameter like /user/:userId and access the userId using ActivatedRoute.
How can you implement a custom form control that works seamlessly with Form Groups and Form Arrays?
- Create a custom component-based form control
- Extend the AbstractControl class
- Implement a custom validator function
- Use the FormBuilder service to create the control
To implement a custom form control that works seamlessly with Form Groups and Form Arrays in Angular, you should create a custom component-based form control.
How can you create a custom attribute directive in Angular?
- By configuring a module
- By extending a class
- Using a service
- Via an HTML element
You can create a custom attribute directive in Angular by extending a class and implementing the necessary logic.
What is the purpose of the ngOnInit lifecycle hook in an Angular component?
- To destroy the component
- To handle HTTP requests and API calls
- To initialize component properties
- To subscribe to observables
The ngOnInit lifecycle hook is used to initialize component properties and perform any setup needed when a component is created.
You are building a shopping cart application using Angular and NgRx. You want to display a smooth animation when items are added to the cart. How would you implement this?
- Use Angular's @HostListener decorator to listen for events and create animations in response to user actions.
- Use Angular's built-in ng-animate directive to create the animation and dispatch a custom action in NgRx to control it.
- Use the @ngrx/effects library to handle animations asynchronously and dispatch an action to trigger the animation.
- Use the @ngrx/router-store library to handle route changes and trigger animations when the route changes.
To implement smooth animations when items are added to the cart in an NgRx-based Angular application, you can use the @ngrx/effects library to handle animations asynchronously. By dispatching an action to trigger the animation, you can ensure smooth and non-blocking animations in the shopping cart.
Which RxJS operator is used to transform the items emitted by an Observable?
- map
- of
- pipe
- subscribe
The correct RxJS operator used to transform the items emitted by an Observable is map. It allows you to apply a function to each emitted item and return the transformed item.