@angular/core

What is @angular/core?

The @angular/core package is a fundamental part of Angular, a popular front-end web application platform. It provides the critical runtime parts of the Angular framework, including the component decorator, directives, dependency injection, and the core Angular APIs necessary for building dynamic single-page web applications.

What are @angular/core's main functionalities?

Components

Components are the building blocks of Angular applications. They control a patch of screen called a view. The @Component decorator indicates that the class immediately below it is a component and provides metadata about the component.

"@Component({ selector: 'app-root', templateUrl: './app.component.html', styleUrls: ['./app.component.css'] }) export class AppComponent { title = 'My Angular App'; }"

Dependency Injection

Dependency Injection (DI) is a design pattern used in Angular to make components or classes dependent on interfaces rather than concrete implementations. This improves modularity and testability.

"constructor(private myService: MyService) {}"

Directives

Directives are classes that add additional behavior to elements in your Angular applications. With Angular's built-in directives, you can manage forms, lists, styles, and what users see.

"@Directive({ selector: '[appHighlight]' }) export class HighlightDirective { constructor(el: ElementRef) { el.nativeElement.style.backgroundColor = 'yellow'; } }"

Other packages similar to @angular/core

react

React is a popular JavaScript library for building user interfaces. It focuses on a component-based architecture similar to Angular but uses a different syntax and design philosophy. React emphasizes a one-way data flow and virtual DOM for efficient rendering.

vue

Vue.js is a progressive JavaScript framework used for building UIs and single-page applications. It is designed from the ground up to be incrementally adoptable. Vue also focuses on the ViewModel part of the MVVM pattern and employs a reactive and composable data model.

README

Angular

The sources for this package are in the main Angular repo. Please file issues and pull requests against that repo.

Usage information and reference details can be found in Angular documentation.

License: MIT

Changelog

19.2.0-next.1 (2025-01-29)

core

| Commit | Type | Description | | -- | -- | -- | | 168516462a9 | feat | support default value in resource() (#59655) | | 6c92d653493 | fix | add hasValue narrowing to ResourceRef (#59708) | | 96e602ebe9c | fix | cancel in-progress request when same value is assigned (#59280) | | cf9054248d1 | fix | check whether application is destroyed before printing hydration stats (#59716) | | 82876242e55 | fix | ensure type is preserved during HMR (#59700) | | 127fc0dc847 | fix | fix resource()'s previous.state (#59708) | | f862ace1819 | fix | fixes test timer-based test flakiness in CI (#59674) |

elements

| Commit | Type | Description | | -- | -- | -- | | 0c1ecb453c8 | fix | not setting initial value on signal-based input (#59773) |

platform-browser

| Commit | Type | Description | | -- | -- | -- | | e6cb411e439 | fix | automatically disable animations on the server (#59762) | | 6b09716754b | fix | prepend baseHref to sourceMappingURL in CSS content (#59730) | | fd7ee47bf70 | fix | Update pseudoevent created by createMouseSpecialEvent to populate _originalEvent property (#59690) | | 65cf061feb4 | fix | Update pseudoevent created by createMouseSpecialEvent to populate _originalEvent property (#59690) | | af9d74710c4 | fix | Update pseudoevent created by createMouseSpecialEvent to populate _originalEvent property (#59690) |

platform-server

| Commit | Type | Description | | -- | -- | -- | | fc5d187da5e | fix | decouple server from animations module (#59762) |

router

| Commit | Type | Description | | -- | -- | -- | | c7b6e1107c6 | fix | prevent error handling when injector is destroyed (#59457) |

service-worker

| Commit | Type | Description | | -- | -- | -- | | e2987a1d4ab | fix | add missing rxjs peer dependency (#59747) |

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