javascript / beginner
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
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export class UserComponent {constructor(private userService: UserService) {}}
angular
Breakdown
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constructor(...)
The constructor is the place where you declare which dependencies the component needs.
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private userService: UserService
The 'private' keyword tells Angular to automatically create a property and assign the injected service to it.