You are building a registration form and want to ensure that the password and confirm password fields match. Which approach would you use to validate this?
- Use a simple JavaScript function to compare the fields.
- Use the Reactive Forms approach with custom validators.
- Use the Template-Driven Forms approach with ngModel binding.
- Use the Validator Functions provided by Angular.
To ensure that the password and confirm password fields match in an Angular registration form, you should use the Reactive Forms approach with custom validators. This allows for more complex validation logic and better user feedback.
How can you identify and select a specific element on a webpage in a Protractor test?
- browser.selectElement()
- element(by.css())
- element(by.model())
- findElement(By.id())
To identify and select an element on a webpage in Protractor, you can use the element(by.css()) method, specifying a CSS selector.
How can you prevent memory leaks related to observables when using the async pipe in Angular?
- Angular automatically handles memory leaks with the async pipe.
- Manually unsubscribing from the observable when it's no longer needed.
- There's no way to prevent memory leaks when using the async pipe.
- Using the ngOnDestroy lifecycle hook to unsubscribe from observables.
To prevent memory leaks when using the async pipe in Angular, you should use the ngOnDestroy lifecycle hook to unsubscribe from observables. Failing to unsubscribe from observables can lead to memory leaks, so it's essential to clean up resources properly.
To check if a form control's value has been changed by the user, you can check the _____ property.
- dirty
- pristine
- touched
- value
To check if a form control's value has been changed by the user, you can check the dirty property. The "dirty" state means the control has been touched or modified.
In Angular, you can group together multiple form controls into a single logical unit using _____ .
- ControlUnit
- FormControlGroup
- FormDirective
- FormGroup
In Angular, you can group together multiple form controls into a single logical unit using a FormGroup.
In template-driven forms, how can you customize the update trigger for form controls?
- By using the ControlValueAccessor interface
- By using the FormsModule module
- By using the HTTPInterceptor interface
- By using the ReactiveForms module
In template-driven forms, you can customize the update trigger for form controls by implementing the ControlValueAccessor interface, which allows you to define custom behavior for control updates.
How can you ensure that an Observable sequence retries a specific number of times after encountering an error before finally failing?
- catchError with a custom error handler
- finalize with a custom completion handler
- repeatWhen with a custom completion handler
- retryWhen with a custom error handler
To ensure that an Observable sequence retries a specific number of times after an error, you can use the retryWhen operator with a custom error handler.
The _____ decorator allows you to access route parameters within an Angular component.
- ActivatedRoute
- ParamInjector
- RouteParam
- RouterParam
The ActivatedRoute decorator allows you to access route parameters within an Angular component and retrieve data from the URL.
What type of data binding is used when you want to send data from a component's class to its template?
- Event binding
- Interpolation binding
- One-way data binding
- Two-way data binding
In Angular, Two-way data binding is used when you want to send data from a component's class to its template, allowing data to flow in both directions between the component and the template.
When you want to bind a DOM event to a method in your component class, you use event binding.
- event binding
- interpolation binding
- property binding
- two-way binding
In Angular, event binding is used to bind a DOM event to a method in your component class, allowing you to respond to user interactions.