angular call service from component code example

Example 1: angular create a service

>>> ng generate service service_name
or
>>> ng generate service /folder-name/service-name

Example 2: calling angular component method in service

// -------------------------------------------------------------------------------------
// codes for component
import { JustAService} from '../justAService.service';
@Component({
  selector: 'app-cute-little',
  templateUrl: './cute-little.component.html',
  styleUrls: ['./cute-little.component.css']
})
export class CuteLittleComponent implements OnInit {
  s: JustAService;
  a: number = 10;
  constructor(theService: JustAService) {
    this.s = theService;
  }

  ngOnInit() {
    this.s.onSomethingHappended(this.doThis.bind(this));
  }

  doThis() {
    this.a++;
    console.log('yuppiiiii, ', this.a);
  }
}
// -------------------------------------------------------------------------------------
// codes for service
@Injectable({
  providedIn: 'root'
})
export class JustAService { 
  private myFunc: () => void;
  onSomethingHappended(fn: () => void) {
    this.myFunc = fn;
    // from now on, call myFunc wherever you want inside this service
  }
}

Example 3: angular import service

import { <service name>Service } from '../<service path>';

Example 4: angular how to use service in class

import { <service name>Service } from '../<service path>';
you can inject service in components constructor:
constructor(public anyService: Service){}