To create a dynamic form in Angular, developers often use the ____ class to programmatically add form controls.
- FormArray
- FormControl
- FormGroup
- NgForm
To create a dynamic form in Angular, developers often use the FormArray class to programmatically add form controls. A FormArray is used when you need to manage a list of form controls.
You are building a complex form that needs to enable or disable sections of the form based on user input. Which type of form would be more suitable to implement this, and why?
- Both are equally suitable
- None of the above
- Reactive forms
- Template-driven forms
To enable or disable sections of a form based on user input, Reactive forms would be more suitable because they provide greater programmatic control and flexibility.
When using Jasmine for unit testing in Angular, what function is used to create a group of related tests?
- afterEach()
- beforeAll()
- describe()
- it()
In Jasmine, the describe() function is used to create a group of related tests, which helps organize and structure your test suite.
In Angular, when using a hot observable, what happens to the data emissions when there are no subscribers?
- Data emissions are buffered and sent to the next subscriber when they subscribe.
- Data emissions are cached and sent to the first subscriber who subscribes.
- Data emissions are lost if there are no subscribers.
- Data emissions are sent to a separate storage location for later retrieval.
When using a hot observable in Angular, data emissions are lost if there are no subscribers. They are not cached or buffered for future subscribers.
You are writing a test for an Angular component that renders a list of items. You want to test that when a new item is added, it is correctly displayed in the component. Which testing technique or utility would be best suited for this?
- End-to-End Testing with Protractor
- Integration Testing with Karma and Jasmine
- No testing needed - it's an Angular feature
- Unit Testing with TestBed
For testing component behavior in isolation, Unit Testing with TestBed is the most suitable approach. It allows you to create an isolated testing environment for the component.
The _____ method in a Route Guard is used to check whether a user can navigate to a specific route.
- canActivate
- canDeactivate
- canNavigateTo
- checkRouteAccess
The canActivate method in a Route Guard is used to check whether a user can navigate to a specific route by returning true or false based on certain conditions.
What is the primary purpose of Dependency Injection (DI) in Angular?
- Define component behavior
- Enable two-way data binding
- Handle HTTP requests
- Manage external dependencies
The primary purpose of Dependency Injection (DI) in Angular is to manage external dependencies by providing them to a component when it's created.
What are the implications of importing a module that provides a service into multiple feature modules?
- Compilation error
- Multiple service instances
- No implications
- Shared singleton service instance
Importing a module with a service into multiple feature modules results in a shared singleton service instance, allowing data to be shared.
How does Angular Universal improve the perceived performance of an application?
- It enhances routing performance
- It improves code quality
- It reduces the bundle size
- It speeds up the initial rendering of a page
Angular Universal improves the perceived performance of an application by speeding up the initial rendering of a page on the server side.
In an Angular application, you want to ensure that data for a specific route is fetched and ready before the route is activated. How would you achieve this?
- Configure route preloading strategies to ensure data is available before route activation.
- Fetch data in the route component's constructor and use a loading spinner until it's available.
- Implement a global data service to fetch data, and check data availability in the route's lifecycle hooks.
- Use route resolvers to fetch and resolve the data before activating the route.
To ensure that data for a specific route is fetched and ready before the route is activated, you should use route resolvers. Resolvers fetch and resolve the data before activating the route, ensuring the data is available when the route component is initialized.