Which command or flag should you use with Angular CLI if you want to analyze the size of your bundles?
- "ng analyze"
- "ng build --stats-json"
- "ng bundle-analysis"
- "ng size-check"
To analyze the size of your bundles in an Angular application, you should use the "ng analyze" command. This command provides detailed information about the size of your application's bundles, including dependencies and modules.
A service provided at the component level will create a new instance for each ________ of the component.
- 'child component'
- 'function'
- 'instance'
- 'module'
A service provided at the component level will create a new instance for each 'instance' of the component. This means that every time a new instance of the component is created, a new instance of the service will also be created, ensuring that each component instance has its own isolated instance of the service.
Which operator is best suited for handling multiple click events in rapid succession with RxJS in Angular?
- debounceTime()
- filter()
- map()
- switchMap()
The debounceTime() operator in RxJS is best suited for handling multiple click events in rapid succession. It allows you to specify a time window during which it will ignore subsequent events, which is ideal for scenarios where you want to debounce click events to avoid processing them too quickly. The other operators have different use cases and are not specifically designed for this scenario.
You are building an e-commerce application. On the product page, you want to have tabs for "Details", "Reviews", and "Related Products", each being a separate route. How would you structure this in Angular?
- Create child routes for each tab within the product page route
- Create separate components for each tab and load them dynamically
- Use one route and manage tab switching with ngIf
- Use route guards to load content on demand
In this scenario, it's best to create child routes for each tab within the product page route. This approach allows you to have separate components and templates for each tab while maintaining a clean URL structure.
The process of retrieving previous navigation details, such as the previously visited route, can be achieved using router.________ in Angular.
- router.events
- router.history
- router.previousRoute
- router.snapshot
In Angular, the process of retrieving previous navigation details, including the previously visited route, can be achieved using router.events. This is because router.events emits events related to route navigation, including NavigationEnd events, which can be used to access the previous route or URL and implement custom logic based on it.
You have a component that receives a large list of items as an input. You notice performance degradation when items within this list are updated frequently. Which change detection strategy would be most appropriate to address this?
- OnPush Change Detection
- Default Change Detection
- CheckAlways Change Detection
- Detached Change Detection
In this scenario, when dealing with frequent updates to a large list of items, using the OnPush change detection strategy is most appropriate. It allows the component to only re-render when its input properties change or when explicitly triggered, which can significantly improve performance by reducing unnecessary updates. Default change detection (Option 2) checks for changes on every digest cycle, leading to performance issues in this scenario. CheckAlways (Option 3) and Detached (Option 4) are not recommended for typical use cases.
How does Akita differ in its approach to state management compared to NgRx?
- Employs Redux-style pattern with actions and reducers
- Favors a component-based state management approach
- Uses a simpler, more declarative approach
- Utilizes MobX for reactive state management
Akita differs from NgRx by using a simpler and more declarative approach to state management. It provides a straightforward way to manage state in Angular applications without the boilerplate associated with Redux-style patterns.
You have a shared service that maintains user settings. You notice that different parts of the application have different instances of this service. What could be a possible reason?
- Different parts of the application are using different configurations, which require separate instances of the service.
- The application is not using a proper dependency injection framework.
- The shared service is being loaded with lazy loading modules, leading to multiple instances.
- There is a bug in the shared service causing it to create multiple instances.
Different parts of the application may require different configurations or data, which necessitates separate instances of the shared service. This allows each part of the application to have its own instance with specific settings or configurations. It's not a bug or dependency injection issue but rather a design choice to accommodate varying requirements.
You're creating a feedback form where users can rate a product. You want to ensure users provide a rating between 1 to 5. How would you validate the input to ensure values are within this range?
- Use client-side JavaScript to restrict input to values between 1 and 5.
- Implement server-side validation to check the rating before storing it.
- Utilize Angular's Validators to create a custom validation rule for the rating field.
- Allow users to enter any value and provide an error message if it's not within the range after submission.
To validate user input for a rating between 1 to 5 in an Angular form, you would use Angular's Validators to create a custom validation rule (Option 3). This ensures the validation occurs on the client side. Server-side validation (Option 2) is important but doesn't prevent invalid values from being submitted. Option 1 restricts input but doesn't provide feedback, and Option 4 is less user-friendly.
Your application has a dynamic form where fields can be added or removed based on user input. Which feature of Angular's Reactive Forms would you leverage to accomplish this?
- Create a separate component for each dynamic form field.
- Implement dynamic forms using Angular's template-driven approach.
- Use the ngIf directive to conditionally render form fields.
- Utilize form arrays to dynamically add or remove form controls.
In Angular's Reactive Forms, you would leverage form arrays to dynamically add or remove form controls based on user input in a dynamic form. The ngIf directive is more suitable for conditionally rendering existing elements in the DOM, not for dynamically managing form controls. Creating a separate component for each dynamic form field is not the recommended approach for dynamic forms, and Angular's template-driven approach is less flexible in handling dynamic forms than Reactive Forms with form arrays.