Services in Angular
From the Angular cheat sheet · Services & DI · verified Jul 2026
Services
Creating and using Angular services
typescript
// Service with @Injectable
@Injectable({
providedIn: 'root'
})
export class UserService {
constructor(private http: HttpClient) {}
getUsers(): Observable<User[]> {
return this.http.get<User[]>('/api/users');
}
getUser(id: number): Observable<User> {
return this.http.get<User>(\`/api/users/\${id}\`);
}
}
// Using in component
constructor(private userService: UserService) {}
ngOnInit() {
this.userService.getUsers().subscribe(users => {
this.users = users;
});
}💡 Use providedIn: 'root' for singleton services
⚡ Handle errors gracefully with catchError
📌 BehaviorSubject for state management
🔥 Always unsubscribe to prevent memory leaks