@angular/common

What is @angular/common?

The @angular/common package is a core Angular library that provides commonly needed services, pipes, and directives that are essential for application development. It is part of the Angular framework and is used for tasks such as HTTP communication, localization, and various utility functions.

What are @angular/common's main functionalities?

HTTP Client

Provides a simplified API for HTTP functionality which allows performing HTTP requests and handling responses within an Angular application.

import { HttpClientModule } from '@angular/common/http';

@NgModule({
  imports: [
    HttpClientModule
  ]
})
export class AppModule { }

Common Directives

Includes directives like ngIf, ngFor, and ngSwitch which are essential for controlling the rendering of the template.

import { CommonModule } from '@angular/common';

@NgModule({
  imports: [
    CommonModule
  ]
})
export class SharedModule { }

Location Services

Provides services for interacting with the browser's URL. Useful for routing and navigation within an Angular application.

import { Location } from '@angular/common';

@Component({
  selector: 'app-component',
  template: '<p>Current path: {{ location.path() }}</p>'
})
export class AppComponent {
  constructor(public location: Location) { }
}

Date, Currency, and Decimal Pipes

Provides built-in pipes for formatting data such as dates, currency, and numbers.

import { DatePipe, CurrencyPipe, DecimalPipe } from '@angular/common';

@Component({
  selector: 'app-component',
  template: '<p>Today is {{ today | date }}</p><p>Amount: {{ amount | currency }}</p>'
})
export class AppComponent {
  today = new Date();
  amount = 1234.56;
}

Other packages similar to @angular/common

react

React is a JavaScript library for building user interfaces. While it is not a one-to-one comparison with @angular/common, React provides a component-based architecture similar to Angular's directives and services.

vue

Vue.js is a progressive JavaScript framework used for building UIs and single-page applications. It offers similar directives and reactivity systems but is generally considered to be more lightweight and easier to integrate into projects than Angular.

axios

Axios is a promise-based HTTP client for the browser and Node.js. It provides many of the same HTTP client capabilities as the HttpClientModule in @angular/common.

moment

Moment.js is a library for parsing, validating, manipulating, and formatting dates. It is similar to the DatePipe in @angular/common but is a standalone library focused solely on date manipulation.

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

19.0.0-next.7 (2024-09-25)

Breaking Changes

core

• Changes to effect timing which generally has two implications:

  • effects which are triggered outside of change detection run as part of the change detection process instead of as a microtask. Depending on the specifics of application/test setup, this can result in them executing earlier or later (or requiring additional test steps to trigger; see below examples).

  • effects which are triggered during change detection (e.g. by input signals) run earlier, before the component's template.

  We've seen a few common failure cases:

  • Tests which used to rely on the Promise timing of effects now need to await whenStable() or call .detectChanges() in order for effects to run.

  • Tests which use faked clocks may need to fast-forward/flush the clock to cause effects to run.

  • effect()s triggered during CD could rely on the application being fully rendered (for example, they could easily read computed styles, etc). With the change, they run before the component's updates and can get incorrect answers. The recent afterRenderEffect() API is a natural replacement for this style of effect.

  • effect()s which synchronize with the forms system are particularly timing-sensitive and might need to adjust their initialization timing.

• ExperimentalPendingTasks has been renamed to PendingTasks.

core

| Commit | Type | Description | | -- | -- | -- | | fc59e2a7b7 | feat | change effect() execution timing & no-op allowSignalWrites (#57874) | | a7eff3ffaa | feat | mark signal-based query APIs as stable (#57921) | | a1f229850a | feat | migrate ExperimentalPendingTasks to PendingTasks (#57533) | | 950a5540f1 | fix | Ensure the ViewContext is retained after closure minification (#57903) |

language-service

| Commit | Type | Description | | -- | -- | -- | | 7ecfd89592 | fix | The suppress diagnostics option should work for external templates (#57873) |

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