Is there any way to check if source is subscribed?

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Just as the title says, in Angular 2, is there any way to check if source is already subscribed? Because I have to check it before using 

this.subscription.unsubscribe();

This is my code:

this.Source = Rx.Observable.timer(startTime, 60000).timeInterval().pluck('interval');

this.Subscription = this.Source
  .subscribe(data => { something }

and then I want to be sure that it is subscribed before calling unsubscribe()

rxjs5 angular typescript javascript
4 Answers

It seems you can check whether the subscription is closed with 

this.subscription.closed

indicate whether this Subscription has already been unsubscribed.

user_45872810

I had a similar case, I had a if condition with one optional subscribe:

if (languageIsSet) {
   // do things...
} else {
   this.langSub = this.langService.subscribe(lang => { 
      // do things...
   });
}

If you want to call unsubscribe safely (you don't know if is subscribed or not), just initialize the subscription with EMPTY instance:

private langSub: Subscription = Subscription.EMPTY;

Now you can unsubscribe without errors.

user_57569640
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