Stack Overflow
Stack Overflow

Questions tagged [angular]

Questions about Angular (not to be confused with AngularJS), the web framework from Google. Use this tag for Angular questions which are not specific to an individual version. For the older AngularJS (1.x) web framework, use the angularjs tag.

The spiritual successor to the older AngularJS web framework.
(Questions about the older framework should use the tag instead.)

Features and Benefits

Building Blocks of Angular Apps

  • Module: A typical module is a cohesive block of code dedicated to a single purpose. A module exports something of value in that code, typically one thing such as a class.

  • Component: A component is a building block with component metadata. In TypeScript, we'd apply the @Component decorator to attach metadata to the class. This metadata mainly consists of the template or templateUrl, the selector, and the attached styling.

  • Template: We define a Component's view with its companion template. A template is a form of HTML that tells Angular how to render the Component.

  • Metadata: Metadata tells Angular how to process a class.

  • Data Binding: Angular supports data binding, a mechanism for coordinating parts of a template with parts of a component. There are four forms of data-binding syntax:

    • Interpolation: {{value}}
    • Property binding : [property]="value"
    • Event Binding : (event)="handler"
    • Two-way data binding: [(ngModel)]="property"

  • Service: "Service" is a broad category encompassing any value, function or feature that our application needs.

  • Directive: A directive is a class with directive metadata. In TypeScript, we'd apply the @Directive decorator to attach metadata to the class.

  • Dependency Injection: "Dependency Injection" is a way to supply a new instance of a class with the fully-formed dependencies it requires. Most dependencies are services. Angular uses dependency injection to provide new components with the services they need.

  • Pipes: Pipes are used for transforming values from one form to another. Angular offers many built-in pipes. Also, you can create custom pipes too.

See the changelog for latest version information.

As of Nov 2020, the current version is 11.0.0. See the full release schedule on the official GitHub repository. Angular versioning follows Semantic Versioning principles; all major versions feature some breaking changes over the previous ones.

Consider using the Update Guide for tips before changing the version.

Browser Support

  • Latest versions of Chrome, Edge, Firefox, IE, and Safari
  • Tested for older browsers including IE9+ and Android 4.1+

Useful links

Books

Code Editors & IDEs

Rich UI components for Angular

Cross-Platform Development

Related tags

Official Logo:

angular logo

Official Website:

angular.io

253958 questions
575
votes
36 answers

How to get current route

The current docs only talk about getting route params, not the actual route segments. For example, if i want to find the parent of current route, how is that possible?
pdeva
  • 36,445
  • 42
  • 122
  • 154
532
votes
16 answers

*ngIf and *ngFor on same element causing error

I'm having a problem with trying to use Angular's *ngFor and *ngIf on the same element. When trying to loop through the collection in the *ngFor, the collection is seen as null and consequently fails when trying to access its properties in the…
garethdn
  • 10,723
  • 11
  • 48
  • 75
528
votes
18 answers

access key and value of object using *ngFor

I am a bit confused about how to get the key and value of an object in angular2 while using *ngFor for iterating over the object. I know in angular 1.x there is a syntax like ng-repeat="(key, value) in demo" but I don't know how to do the same in…
Pardeep Jain
  • 71,130
  • 29
  • 141
  • 199
518
votes
24 answers

How to detect a route change in Angular?

I am looking to detect a route change in my AppComponent. Thereafter I will check the global user token to see if he is logged in. Then I can redirect the user if he is not logged in.
AngularM
  • 13,932
  • 27
  • 78
  • 151
508
votes
21 answers

No provider for HttpClient

After upgrading from angular 4.4 to 5.0 and after updating all HttpModule and Http to HttpClientModule I started to get this error. I also added HttpModule again to be sure it's not due to some dependency but it doesn't resolve the issue In…
Himmet Yelekin
  • 5,101
  • 2
  • 13
  • 14
484
votes
9 answers

@Directive vs @Component in Angular

What is the difference between @Component and @Directive in Angular? Both of them seem to do the same task and have the same attributes. What are the use cases and when to prefer one over another?
Prasanjit Dey
  • 5,244
  • 3
  • 11
  • 15
469
votes
16 answers

Binding select element to object in Angular

I'd like to bind a select element to a list of objects -- which is easy enough: @Component({ selector: 'myApp', template: `

My Application

Lahiru Chandima
  • 16,832
  • 14
  • 78
  • 137
431
votes
14 answers

How can I get new selection in "select" in Angular 2?

I am using Angular 2 (TypeScript). I want to do something with the new selection, but what I get in onChange() is always the last selection. How can I get the new selection?