You are building a data table component that updates frequently. You want to minimize the performance impact of Angular's change detection mechanism on this component. How would you achieve this?
- Apply the default change detection strategy
- Increase the poll interval
- Optimize the component's HTML structure
- Use OnPush change detection strategy
To minimize the performance impact, you should use the OnPush change detection strategy, which will update the component only when its input properties change.
What is a dynamic form in Angular?
- A form that can change at runtime
- A form that changes its color
- A form that uses 3D graphics
- A form with animated transitions
In Angular, a dynamic form is a form that can change at runtime based on user interactions or application logic. It allows for flexible and customizable forms.
What does a service in Angular typically consist of?
- Component behavior
- Dependency Injection
- HTML and CSS
- Reusable application logic
In Angular, a service typically consists of reusable application logic, such as data manipulation, communication with servers, or shared functionality.
To execute the Observable and start emitting values, you need to call the _____ method.
- emit()
- execute()
- start()
- subscribe()
To execute the Observable and start emitting values, you need to call the subscribe() method. This method subscribes to the Observable and listens for emitted values.
Which RxJS operator is commonly used to filter items emitted by an Observable based on a condition?
- catchError
- filter
- switchMap
- takeUntil
The RxJS operator commonly used to filter items emitted by an Observable based on a condition is filter. It allows you to specify a predicate function to determine which items should be included in the output.
How can you access a specific form control within a form group in Angular?
- Using form.get()
- Using formArray
- Using formControl
- Using formGroup.get()
You can access a specific form control within a form group in Angular by using the **formGroup.get()** method. It allows you to retrieve a form control by its name.
In a real-time data streaming application built with Angular, you want to ensure that multiple components receive the same data from an observable without creating multiple subscriptions. What kind of observable would you use?
- AsyncSubject
- BehaviorSubject
- ReplaySubject
- Subject
To ensure multiple components receive the same data from an observable without multiple subscriptions, you would use a ReplaySubject. It replays the latest emitted value to all new subscribers.
How do you access a specific form control within a Form Array in Angular?
- Using the get method
- Using the setValue method
- Using the subscribe method
- Using the valueChanges property
To access a specific form control within a Form Array in Angular, you can use the get method. It allows you to retrieve the control at a specific index.
How can you handle errors in an Observable stream using RxJS operators?
- catchError()
- filter()
- map()
- mergeMap()
You can handle errors in an Observable stream using the catchError() operator, which allows you to catch and handle errors in the stream.
Which testing framework is commonly used for writing unit tests in Angular applications?
- Jasmine
- Jest
- Mocha
- Protractor
Jasmine is a commonly used testing framework for writing unit tests in Angular applications. It provides a suite of functions to create and run tests.