When testing Angular services, you can replace a real service with a _____ to simulate service behavior.
- component
- mock
- pipe
- spy
When testing Angular services, you can replace a real service with a mock to simulate service behavior and control the service's responses for testing purposes.
Which operator can be used to automatically unsubscribe from an observable when a component is destroyed?
- "map" operator
- "subscribe" operator
- "takeUntil" operator
- "tap" operator
The "takeUntil" operator is commonly used to automatically unsubscribe from an observable when a component is destroyed. It takes an observable that emits when the component is destroyed, ensuring that the original observable is unsubscribed.
A directive that changes the appearance or behavior of a DOM element is known as a(n) _____ directive.
- attribute
- component
- decorator
- structural
A directive that changes the appearance or behavior of a DOM element is known as an attribute directive in Angular.
In a directive, the ________ decorator is used to get a reference to the host element.
- @Directive
- @HostBinding
- @HostListener
- @Injectable
In a directive, the @HostBinding decorator is used to get a reference to the host element, allowing you to access and modify its properties.
Reactive forms in Angular are also known as _____ forms.
- Data-driven forms
- Dynamic forms
- Model-driven forms
- Template forms
Reactive forms in Angular are also known as Model-driven forms, as they focus on creating the model and then binding it to the UI elements.
You're tasked with creating a set of UI components that can be reused in non-Angular projects, such as React or Vue.js applications. Which Angular feature would be most suitable for this task?
- Angular Directives
- Angular Elements
- Angular Modules
- Angular Services
To create UI components that can be reused in non-Angular projects, you can use Angular Elements, which allows you to package Angular components as custom elements that can be used in other frameworks like React or Vue.js.
You are working on an Angular application that uses NgRx for state management. You need to implement a feature where a user action dispatches multiple actions sequentially. How would you achieve this?
- Create a custom service that manually dispatches actions in a sequential manner, and use it in your components.
- Use the mergeMap operator from RxJS to handle the sequential dispatch of actions in an effect.
- Use the pluck operator from RxJS to extract data from the store and dispatch actions sequentially.
- Use the switchMap operator from RxJS to handle the sequential dispatch of actions in an effect.
To achieve sequential dispatch of actions in an NgRx-based Angular application, you can use the mergeMap operator from RxJS within an effect. This operator allows you to handle actions sequentially and maintain the order of dispatch.
A common practice to validate a group of related form controls is to use a custom _____ validator in Angular.
- Reactive Forms
- Reactive Forms
- Template-driven
- Template-driven
In Angular, a common practice to validate a group of related form controls is to use a custom Reactive Forms validator.
How can you dynamically add a new control to a Form Array in Angular?
- formArray.addControl(control)
- formArray.createControl(control)
- formArray.insert(index, control)
- formArray.push(control)
To dynamically add a new control to a Form Array in Angular, you can use the push method, which adds the control to the end of the array.
Which method is used to submit a form in Angular?
- formSubmit()
- ngSubmit()
- postForm()
- submitForm()
In Angular, the method used to submit a form is typically ngSubmit(). It's a commonly used event handler that is triggered when a form is submitted.