Dependency Injection Basics

Snippet

Dependency Injection Basics

Dependency Injection (DI) is a core pattern where a class requests dependencies from external sources rather than creating them. In Angular, you inject services through the constructor.

snippet.js
javascript
export class UserComponent {
  constructor(private userService: UserService) {}
}

angular

Breakdown

constructor(...)

The constructor is the place where you declare which dependencies the component needs.

private userService: UserService

The 'private' keyword tells Angular to automatically create a property and assign the injected service to it.

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Dependency Injection Basics

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