To set up the testing environment before running any test suite in Protractor, you can utilize the _____ function in the configuration file.
- beforeAll
- browser.driver
- onCleanup
- onPrepare
To set up the testing environment before running any test suite in Protractor, you can use the onPrepare function in the configuration file.
How do you track the validity and state of a form control in a template-driven form?
- Using *ngIf directive
- Using [(ngModel)] directive
- Using [formControl] directive
- Using [formState] directive
To track the validity and state of a form control in a template-driven form, you can use the [formControl] directive, which binds the control's state and validity to the template.
You're working on an application that has several feature modules. To improve the user experience, you decide to preload some modules in the background while the user is interacting with the app. How can you implement this behavior?
- Manually load modules using import() as the user interacts with different parts of the app
- Use localStorage to cache module data and preload them when the app loads
- Use the Angular Router Preloading Strategy to preload specific modules
- Utilize a service worker to cache and preload modules as a background process
To improve the user experience by preloading specific modules in the background as the user interacts with the app, you can use the Angular Router Preloading Strategy. It allows you to preload modules when needed, optimizing the app's performance.
You are building a form where certain fields need to be shown or hidden based on the selection of a dropdown. How can you dynamically add or remove validations on these fields based on their visibility?
- Create separate forms for each combination of visible fields.
- Use ngClass to toggle validations dynamically.
- Use ngSwitch to toggle validations based on the dropdown value.
- Use the ngIf directive to conditionally add or remove validators.
To dynamically add or remove validations on fields based on their visibility in an Angular form, you should use the ngIf directive to conditionally add or remove validators. This approach allows for dynamic validation based on UI interactions.
In template-driven forms, the _____ directive is used to create two-way data bindings on an input field.
- *ngFor
- *ngIf
- *ngModel
- *ngSwitch
In template-driven forms, the *ngModel directive is used to create two-way data bindings on an input field, allowing the field to sync its value with a component property.
How can you apply a custom validator to a form control in Angular?
- Applying ngFor directive
- By extending the FormControl class
- Using the async pipe
- Using the ngIf directive
You can apply a custom validator to a form control in Angular by extending the FormControl class and implementing your validation logic within it.
Your Angular application includes a form that users utilize to submit sensitive data. How can you ensure that the form data is only submitted once, even if the user accidentally clicks the submit button multiple times?
- Implement a server-side mechanism that tracks and validates submitted data
- Use a client-side timer to disable the submit button for a fixed duration
- Use client-side JavaScript to check for duplicate submissions
- Utilize Angular guards to prevent multiple form submissions
To ensure that sensitive form data is submitted only once, you should utilize Angular guards to prevent multiple submissions. Angular guards allow you to control navigation and actions within your application.
Imagine you're building an Angular application that involves creating a directive to apply dynamic styling to elements. How can you pass values to your custom directive to make it reusable across different elements?
- Pass values through the DOM using attributes
- Use a service to share data between elements
- Use global variables to store values
- Use the @Input decorator to pass values as input properties
To make a directive reusable across different elements, you should use the @Input decorator to pass values as input properties.
What is the main difference between the combineLatest and withLatestFrom operators in RxJS?
- combineLatest emits only when all sources emit sequentially
- combineLatest emits only when all sources emit simultaneously
- withLatestFrom emits only when all sources emit simultaneously
- withLatestFrom emits when the source emits and the other observable emits, but not necessarily simultaneously
The main difference between combineLatest and withLatestFrom is that combineLatest emits when all sources emit simultaneously, while withLatestFrom emits when the source emits and the other observable emits, but not necessarily simultaneously.
Which RxJS operator would you use to combine multiple Observables into a single Observable?
- combineLatest()
- concatMap()
- reduce()
- switchMap()
To combine multiple Observables into a single Observable, you can use the combineLatest() operator, which emits a new value when any of the source Observables emits a new value.