What is the best way to call a service method from a component in Angular2 with TypeScript?
My service needs to periodically notify components of certain events. Is there a more efficient approach than keeping a reference to the component in the service and calling its methods directly?
Is there a more appropriate or efficient way to achieve this in Angular2?
Thank you.
Implement a subscription mechanism within a component:
@Injectable()
export class DataService {
Subject eventTrigger = new Subject();
triggerEvent() {
this.eventTrigger.next('eventValue');
}
}
@Component({ ...})
export class DisplayComponent {
constructor(dataService:DataService) {
dataService.eventTrigger.subscribe(value => this.displayEventData(value));
}
displayEventData(value) {
console.log("Received value: " + value);
}
}
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