How can you pre-fetch a lazily loaded module so that it's immediately available when the user needs it?
- Configure eager loading for the module in the app's routing configuration.
- Use the canActivate route guard to preload the module.
- Use the loadChildren property to specify a preload attribute.
- Utilize Angular's built-in preloading strategy to load modules in the background.
To pre-fetch a lazily loaded module in Angular so that it's immediately available when the user needs it, you can utilize Angular's built-in preloading strategy. This strategy allows the application to load modules in the background while the user interacts with the initial parts of the application, reducing load times when the user navigates to the lazily loaded module.
You are developing a multi-tenant application where each tenant may require slightly different service implementations. How can you achieve this in Angular without duplicating a lot of code?
- Create separate Angular applications for each tenant, each with its unique service implementation.
- Create separate Angular modules for each tenant with their service implementations.
- Duplicate the service code for each tenant and load the respective service based on the tenant's login.
- Use Angular dependency injection to provide different service instances based on the tenant context.
In a multi-tenant Angular application, you can use Angular's dependency injection to provide different service instances based on the tenant context. This avoids code duplication and maintains a modular and maintainable codebase. Creating separate modules for each tenant can also work but may be less dynamic and flexible than using dependency injection.
In terms of performance optimization, why is Ahead-of-Time (AOT) compilation beneficial for Angular applications?
- AOT allows for better code splitting and lazy loading
- AOT enhances the developer experience by enabling hot module reloading
- AOT improves runtime execution speed through just-in-time compilation
- AOT reduces the bundle size by eliminating the need for the Angular compiler in the browser
Ahead-of-Time (AOT) compilation in Angular is beneficial for performance optimization because it reduces the bundle size by precompiling templates and removing the need for the Angular compiler to be shipped to the browser. Smaller bundles result in faster loading times for the application.
To dynamically create a component and attach it to a specific location in the view, you'd use the ______ along with ComponentFactoryResolver.
- ComponentLoader
- DynamicInjector
- ViewChild
- ViewContainerRef
To dynamically create and attach components in Angular, you use the ViewContainerRef along with ComponentFactoryResolver. ViewContainerRef provides access to the view where you want to insert the component, and ComponentFactoryResolver helps create and manage the component instance. ViewChild is a decorator used to access child components, but it's not directly related to creating components dynamically. ComponentLoader and DynamicInjector are not standard Angular concepts in this context.
When you want to run logic before a route's data is resolved, you should implement the Resolve<________> interface in Angular.
- Resolve
- Resolve
- Resolve
- Resolve
In Angular, when you want to run logic before a route's data is resolved, you should implement the Resolve interface. This allows you to define a resolver service that can fetch data or perform actions before the route is activated, ensuring that the required data is available when the route component is loaded.
Which method of ViewContainerRef allows you to insert a component?
- createComponent()
- deleteComponent()
- updateComponent()
- renderComponent()
The method of ViewContainerRef that allows you to insert a component is createComponent(). This method is used to create and insert a dynamic component into the specified view container. The other options are not valid methods of ViewContainerRef and do not serve the purpose of inserting components.
How can you simulate a click event on an element during Angular unit testing?
- Angular unit tests cannot simulate click events.
- By manually dispatching a click event on the DOM element.
- Using the click method provided by the TestBed utility.
- Using the simulateClick function from the @angular/testing package.
To simulate a click event on an element during Angular unit testing, you can manually dispatch a click event on the DOM element using the dispatchEvent method. This allows you to trigger the same behavior that a real user would experience when clicking the element.
What tool is responsible for executing tests in a browser when testing Angular applications?
- Istanbul
- Jasmine
- Karma
- Protractor
Karma is a test runner tool that is responsible for executing tests in a browser when testing Angular applications. It launches the browser, captures it, and runs the tests in a real browser environment, allowing you to test your application as it would run in production.
What is the main purpose of Angular's ngIf directive?
- To create a new Angular component.
- To conditionally show or hide elements.
- To define a route in an Angular application.
- To style Angular components.
The primary purpose of Angular's ngIf directive is to conditionally show or hide elements in the DOM based on a given condition. This is useful for displaying or hiding parts of a user interface depending on the application's state or user interactions. The other options do not accurately describe the main purpose of ngIf.
To update your Angular CLI globally to the latest version, you would use the command npm install -g ________.
- @angular/cli
- angular
- ng
- typescript
To update your Angular CLI globally to the latest version, you would use the command npm install -g @angular/cli. This command installs or updates the Angular CLI package globally, ensuring you have the latest version available.