Which tool is commonly used for executing unit tests in Angular applications?
- Karma
- Protractor
- TypeScript
- Webpack
The commonly used tool for executing unit tests in Angular applications is Karma. Karma is a test runner that is often used with Angular for running unit tests.
The 'canLoad' Route Guard method checks whether a _____ can be loaded lazily.
- component
- directive
- module
- service
The 'canLoad' Route Guard method checks whether a module can be loaded lazily. It's used to control the lazy loading of feature modules in Angular applications.
When a subscriber attaches to a cold observable, it gets its own independent execution of the _____.
- Observable
- Operator
- Stream
- Subscription
When a subscriber attaches to a cold observable, it gets its own independent execution of the Observable. A new instance of the observable's execution is created for each subscriber.
How can you handle conditional validation for controls within a Form Array in Angular?
- Define custom validation directives
- Use a separate Form Array for each condition
- Use the FormControl's setValidators method
- Utilize the Validators.compose function
You can handle conditional validation in Angular for controls within a Form Array by using the setValidators method of the FormControl.
Which Angular CLI command is used to create a new Angular project?
- ng create project
- ng generate project
- ng new
- ng start project
The command to create a new Angular project using Angular CLI is ng new. It sets up a new Angular project with the necessary files and dependencies.
In Angular, how can you ensure that your service correctly handles HTTP errors during testing?
- Mock the HttpClient responses
- Use a delay operator like debounceTime for error cases
- Use real HTTP requests with a testing server
- Wrap the service call in a try-catch block
To ensure that your Angular service correctly handles HTTP errors during testing, you should mock the HttpClient responses. This allows you to control the responses and simulate error scenarios in a controlled environment. Using real HTTP requests or delay operators like debounceTime is not recommended for testing HTTP error handling.
Angular Elements are packaged as custom elements, a web standard for defining new HTML elements in a _____.
- Directive
- Module
- Service
- Shadow DOM
Angular Elements are packaged as custom elements, utilizing the web standard for defining new HTML elements in the Shadow DOM.
How can you make a route parameter optional in Angular?
- Add a "?" to the parameter
- Use a default value
- Use a wildcard route
- Use a regex pattern
You can make a route parameter optional in Angular by adding a "?" to the parameter name in the route configuration. This indicates that the parameter is optional, and the route can still be matched without it.
How can you dynamically add or remove form controls in an Angular form?
- Use *ngFor Directive
- Use Angular Material Form
- Use FormGroup API
- Use Reactive Forms Module
To dynamically add or remove form controls in an Angular form, you can use the FormGroup API. It allows you to add, remove, or manipulate form controls within a FormGroup dynamically based on user interactions or other criteria.
In an e-commerce application, you want to fetch product details and customer reviews concurrently, and only update the UI when both pieces of data are available. Which RxJS operator should you use?
- combineLatest
- forkJoin
- mergeMap
- zip
To fetch data concurrently and update the UI when both are available, you should use the forkJoin operator, which waits for all observables to complete and then emits their last values as an array.