Here is a solution presented from a student named Henry Goh on how to unsubscribe from an Angular 4 subscription:
Import the OnDestroy and Subject classes
import { Component, OnInit, OnDestroy } from "@angular/core";
import { Observable, Subject } from "rxjs/Rx";
import { Observable, Subject } from "rxjs/Rx";
Implement the OnDestroy class
export class DocumentsComponent implements OnInit, OnDestroy
Add a new field in your DocumentsComponent class
ngUnsubscribe: Subject<void> = new Subject<void>();
In ngOnInit(), call the takeUntil method and insert the new field as argument.
ngOnInit() {
const timer = Observable.timer(0, 5000);
timer.takeUntil(this.ngUnsubscribe)
.subscribe(() => { this.getDocuments(); });
}
const timer = Observable.timer(0, 5000);
timer.takeUntil(this.ngUnsubscribe)
.subscribe(() => { this.getDocuments(); });
}
5. Implement the ngOnDestroy() method
ngOnDestroy() {
this.ngUnsubscribe.next();
this.ngUnsubscribe.complete();
}
this.ngUnsubscribe.next();
this.ngUnsubscribe.complete();
}
