MEAN Angular Routing and Forms 5

Question 1

Which Angular form validator would you use to ensure an input matches a specific regular expression pattern?

Accepted Answer

Validators.pattern()

Answer

Validators.pattern() accepts a string or RegExp and validates that the control's value matches the given pattern.

Question 2

What is the role of a Route Resolver in Angular?

Accepted Answer

It pre-fetches data before the target component is activated

Answer

A Resolver fetches data from a service before the route activates, so the component receives the data immediately without needing a loading state.

Question 3

In Angular template-driven forms, what attribute is required on a form control for Angular to track it as part of the form model?

Accepted Answer

ngModel

Answer

The ngModel directive registers the element with the parent NgForm, making it part of the template-driven form model and enabling two-way data binding.

Question 4

What does Angular's `preloadingStrategy: PreloadAllModules` do when configured in RouterModule?

Accepted Answer

Loads lazy modules in the background after the initial navigation completes

Answer

PreloadAllModules causes Angular to start downloading all lazy-loaded modules in the background after the initial route loads, improving subsequent navigation speed.

Question 5

How do you access the value of a nested FormGroup control named 'city' inside a 'address' FormGroup in Angular reactive forms?

Accepted Answer

form.get('address.city')

Answer

The get() method on AbstractControl accepts a dot-notation path string to access deeply nested controls within a FormGroup.

MEAN - Stack Development Practice Test

MEAN - Stack Development Practice Test

MEAN Angular Routing and Forms 5