The ______ is a container where one or more views can be attached to a component.
- ComponentContainer
- ComponentHolder
- ComponentView
- ViewContainer
The ViewContainer is a container where one or more views can be attached to a component. Views can be dynamically created and added to this container, allowing for dynamic rendering of components in frameworks like Angular. Understanding how to use ViewContainers is crucial for creating dynamic user interfaces.
You are tasked with ensuring that specific headers are added to every HTTP request in your Angular application. How would you achieve this?
- Create an HTTP interceptor
- Manually add headers to each request
- Modify the Angular configuration file
- Use a service to add headers
To ensure specific headers are added to every HTTP request, you should create an HTTP interceptor. Interceptors allow you to intercept outgoing requests and modify them, making it a suitable choice for adding headers uniformly to requests across your Angular application.
What command would you use to generate a new module and its associated routing in a single command using Angular CLI?
- ng create module my-module --routing
- ng generate module my-module --routing
- ng module generate my-module --with-routing
- ng new my-app --module my-module
To generate a new module with its associated routing in a single command using Angular CLI, you should use the ng generate module my-module --routing command. This command creates a new module and sets up its routing configuration simultaneously, which is a common practice in Angular applications.
When testing asynchronous operations in Angular, which utility can be used to handle asynchronous tasks inside test specs?
- ComponentFixture
- HttpClientTestingModule
- TestBed.overrideProvider()
- async()
When testing asynchronous operations in Angular, the async() function is used to handle asynchronous tasks inside test specs. It enables you to write asynchronous code in a synchronous style, making it easier to work with observables, promises, and async functions within your tests.
If you want to project content but also need to wrap it with additional styling or behavior, you might consider using ________ instead of plain content projection.
- Encapsulation
- Inheritance
- Transclusion
- Transpilation
If you want to project content but also need to wrap it with additional styling or behavior, you might consider using Transclusion instead of plain content projection. Transclusion allows you to wrap the projected content with additional HTML, CSS, or behavior while preserving the original content. It is a technique commonly used in Angular for creating reusable components.
If you want to prevent navigation away from a component under certain conditions, which Route Guard would you use?
- CanActivate
- CanActivateChild
- CanDeactivate
- CanLoad
To prevent navigation away from a component under certain conditions, you would use the 'CanDeactivate' Route Guard. This guard allows you to check if it's safe to leave the current route or component and can be useful for scenarios like unsaved changes in a form where you want to confirm with the user before leaving the page. The other guards serve different purposes, such as allowing or denying access to routes or modules.
Consider a scenario where you have multiple slots in a component. How can you ensure that specific content from a parent component is projected into the right slot?
- By using the select attribute with the
element. - By specifying the slot name in the content property of the parent component.
- By using Angular directives like *ngIf and *ngFor.
- By utilizing the ng-content service for slot management.
In Angular, you can ensure that specific content is projected into the right slot by using the select attribute with the element. This attribute allows you to specify a CSS selector to target the desired slot based on the parent component's content. This approach provides fine-grained control over content projection. The other options are not the primary means to control slot projection.
What does 'View Encapsulation' in Angular control?
- Code optimization
- Data encapsulation
- Routing configuration
- Styling scoping
'View Encapsulation' in Angular controls the scoping of styles for a component. It determines whether the styles defined in a component's styleUrls or inline styles are scoped to that component only or affect the entire application. It helps prevent style leakage and conflicts.
Which directive in template-driven forms is used to display specific error messages based on validation failures?
- *ngFor directive.
- *ngIf directive.
- *ngSwitch directive.
- *ngTemplateOutlet directive.
In template-driven forms, the *ngIf directive is used to conditionally display error messages based on validation failures. You can use it to check the control's validity and display custom error messages as needed. The other directives listed have different purposes and are not typically used for displaying validation errors in template-driven forms.
What is the role of Value Accessors in Angular forms?
- They control the overall form structure.
- They facilitate communication between custom form controls and the forms module.
- They manage the rendering of form controls on the UI.
- They provide built-in validation functions.
The role of Value Accessors in Angular forms is to facilitate communication between custom form controls and the forms module. They enable custom form controls to interact seamlessly with Angular's reactive forms, allowing them to manage their values, validation, and integration into the overall form structure. Value Accessors are essential for custom form control development in Angular.