Services berisi logic bisnis, dan Dependency Injection menyediakannya ke komponen.

Membuat Service

@Injectable({ providedIn: "root" })
export class DataService {
  private items: string[] = []

  getItems(): string[] {
    return this.items
  }

  addItem(item: string): void {
    this.items.push(item)
  }
}

Menggunakan Service

@Component({
  template: `
    @for (item of items; track $index) {
      <p>{{ item }}</p>
    }
  `,
})
export class ListComponent {
  items: string[]

  constructor(private dataService: DataService) {
    this.items = this.dataService.getItems()
  }
}

providedIn: "root" menjadikan service singleton di seluruh aplikasi.