10+ Byas Foto World Interview Questions and Answers

Passing data between parent and child components is component interaction in Angular.

• Use @Input decorator to pass data from parent to child component

• Use @Output decorator and EventEmitter to pass data from child to parent component

• Use services to share data between components

• Use ViewChild to access child component's properties and methods from parent component

Life cycle hooks are methods that get called at specific stages of a component's life cycle.

• ngOnInit() - called after the component is initialized

• ngOnChanges() - called when the component's input properties change

• ngOnDestroy() - called just before the component is destroyed

• Used to perform specific actions at different stages of a component's life cycle

• Yes, I have worked on them in my project

The latest version of TypeScript used in my project has several new features.

• Optional Chaining and Nullish Coalescing

• Improved performance with faster compilation times

• Support for private fields and methods

• Higher order type inference from generic constructors

• Support for ECMAScript private fields

• Improved support for tuples

• Smaller bundle sizes with tree shaking

Angular has four types of data bindings: Interpolation, Property binding, Event binding, and Two-way binding.

• Interpolation: {{ expression }}

• Property binding: [property]="expression"

• Event binding: (event)="expression"

• Two-way binding: [(ngModel)]="expression"

To call REST APIs in Angular, use the HttpClient module and its methods like get(), post(), put(), delete().

• Import the HttpClientModule in your Angular module

• Inject the HttpClient service in your component or service

• Use the HttpClient methods to make HTTP requests to the REST APIs

• Handle the response using observables and subscribe to them

• Example: httpClient.get('https://api.example.com/data')

• Example: httpClient.post('https://api.example.com/data', postData)

Routing is the process of navigating between different components or pages in an Angular application.

• Routing is used to create single-page applications (SPAs) where the content is dynamically loaded without refreshing the entire page.

• In Angular, routing is achieved using the RouterModule and the RouterLink directives.

• The RouterModule is imported from the @angular/router package and added to the imports array of the app module.

• Routes are defined as an array of objects, where e...read more

Lazy loading is a technique in Angular that loads modules or components on-demand, improving performance.

• Lazy loading helps reduce initial load time by loading modules or components only when needed

• It improves performance by splitting the application into smaller chunks

• Syntax: import() function is used to dynamically load modules or components

Observable is for handling multiple values over time, while Promise is for handling a single value.

• Observable can emit multiple values over time, while Promise can only emit a single value.

• Observable can be cancelled, while Promise cannot be cancelled.

• Observable provides operators for transforming and combining data, while Promise does not have such operators.

• Observable is lazy, meaning it won't start emitting values until someone subscribes to it, while Promise starts execut...read more

The @Input() and @Output() are decorators in Angular used for communication between parent and child components.

• The @Input() decorator is used to pass data from a parent component to a child component.

• The @Output() decorator is used to emit events from a child component to a parent component.

• The @Input() property is bound to a value in the parent component template using property binding.

• The @Output() property is bound to an event in the child component template using event b...read more