How to call a function in a component from service directly?

Question

Is there any option to execute method in a component from a service directly?

@Component({
  selector:'component'
})
export class Component{
  function2(id){ 
    console.log('ID printed '+ id);
  }
}


@Injectable()

export class Service {
  callfunction2() {
    //how?;
      }
}

No, because that would be the opposite of how components and services should interact (components should call services, not vice-versa). — Heretic Monkey, May 30 '19 at 15:43
Technically it is possible with injectors, but don't do it (for the reasons listed in the comment above) — Daniel, May 30 '19 at 15:43
Possible duplicate of [Angular service call function in component](https://stackoverflow.com/questions/36309837/angular-service-call-function-in-component) — Heretic Monkey, May 30 '19 at 15:49

score 1 · Answer 1 · answered May 30 '19 at 15:47

You shouldn't call a component function from a service.

You could however create a Subject in the service, and subscribe to it from the component.

In that case once callfunction2 is passed, it emits the id value on the Subject, and any components that subscribe to this Subject will receive the value

@Component({
  selector:'component'
})
export class Component{

  constructor(private service: Service) {}

  function2(id){
    this.service.subject.subscribe(id => {
        console.log('ID printed ' + id);
    });
  }
}


@Injectable()

export class Service {

  public subject: Subject<any> = new Subject<any>();

  callfunction2(id) {
    this.subject.next(id);
  }
}

How to call a function in a component from service directly?

1 Answers1