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Overview

Angular Basics

All Angular Basics

What is Angular?

What is the difference between Angular and AngularJS?

What is a standalone component?

What are Angular modules?

What is a decorator?

What is a component lifecycle?

What is data binding in Angular?

What is the difference between property and attribute binding?

What are directives?

What are pipes?

Components

All Components

What is the difference between a component and a directive?

How do `@Input` and `@Output` work?

What is `EventEmitter` used for?

What is content projection?

What is `ViewChild`?

What is the difference between view and content children?

How do lifecycle hooks work?

What is the `OnPush` change-detection strategy?

How do you build a reusable Angular component?

How do you communicate between sibling components?

Services

All Services

What is an Angular service?

Why are services usually injectable?

What does `providedIn: root` mean?

What is the difference between a service and a factory provider?

How do you share state with a service?

How do you test an Angular service?

What is `HttpClient`?

How do HTTP interceptors work?

How do you handle HTTP errors?

When should a service be stateless?

Dependency Injection

All Dependency Injection

What is dependency injection?

What is an injector?

What are provider scopes?

What is an injection token?

What are multi-providers?

How does hierarchical DI work?

What is `@Optional`?

What is `@Self` and `@SkipSelf`?

How do you provide a configuration object?

How do you mock a dependency in a test?

RxJS

All RxJS

Difference between Subject and BehaviorSubject

What is the difference between an Observable and a Promise?

What is a Subject?

What is the difference between Subject and BehaviorSubject?

What is a ReplaySubject?

What is the difference between `switchMap`, `mergeMap`, `concatMap`, and `exhaustMap`?

What do `debounceTime` and `distinctUntilChanged` do?

How do you unsubscribe safely?

What is the `async` pipe?

How do you handle errors in RxJS?

Routing

All Routing

How does Angular Router work?

What is a router outlet?

What are route parameters and query parameters?

What are route guards?

What is lazy loading?

What are resolvers?

How do you create child routes?

How do you redirect routes?

How do you handle a not-found route?

How do you preload lazy modules?

State Management

All State Management

How do you manage state in Angular?

When is a service with RxJS enough?

What is NgRx?

What are actions, reducers, selectors, and effects?

Why should reducers be pure?

How do selectors improve performance?

How do you model loading and error state?

What is entity state normalization?

How do signals fit state management?

When should you avoid a global store?

Angular Signals

All Angular Signals

What are Angular Signals?

What is the difference between `signal`, `computed`, and `effect`?

How do signals work with OnPush?

How do you update a writable signal?

What is a computed signal?

When should you use an effect?

How do signals interoperate with RxJS?

What are signal inputs?

How do you avoid effects that write state?

When should you use a signal instead of an Observable?

Performance

All Performance

How does Angular change detection work?

What does `OnPush` change detection do?

How do you track list items efficiently?

How do you avoid expensive template expressions?

How do pure pipes improve performance?

How do you lazy load a feature?

How do you profile an Angular app?

What is zone.js and what role does it play?

How do you reduce bundle size?

How do you prevent memory leaks in Angular?

Angular Architecture

All Angular Architecture

How do you structure a large Angular application?

What is feature-based architecture?

How do you design a shared module or shared library?

How do you separate smart and presentational components?

How do you organize core services?

How do you create reusable form controls?

How do you define API models and mappers?

How do you handle application-wide errors?

How do you test Angular components and services?

How do you migrate an Angular application safely?

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Dependency Injection

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