Menu
private customer: Subject<Object> = new BehaviorSubject<Object>(null); setCustomer(id, accountClassCode) { this.customer.next({'id': id, 'accountClassCode': accountClassCode}); } getCustomer() { return this.customer.asObservable(); } I'm using this part of code but I'm getting an error that can not find id of null. Is there any solution to get initial value that is not null?
983
subscribe(num => console. log('last: ' + num)); If you don't want your stream to end, but you do want subscribers to receive the last value emitted before subscription, consider reaching for BehaviorSubject , which was designed for this use case.
So the only solution that I found to get the value of a BehaviorSubject was: let value; myBehaviorSubject. take(1). subscribe( (e) => value = e );
A BehaviorSubject holds one value (so we actually need to initialize a default value). When it is subscribed it emits that value immediately. A Subject on the other hand, does not hold a value.
The purpose of BehaviorSubject is to provide initial value. It can be null or anything else. If no valid initial value can be provided (when user id isn't known yet), it shouldn't be used.
ReplaySubject(1) provides a similar behaviour (emits last value on subscription) but doesn't have initial value until it is set with next.
It likely should be
private customer: Subject<Object> = new ReplaySubject<Object>(1); If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
