rxjs-pipeable-operators

问题 I am working on an app using Angular 9 and RxJS 6.5. The functionality I have problems with uses Angular services to fetch some data from a server and provides this data to views (using RxJS behaviorSubjects). Before passing that data to the views though, I want to do some unit conversion, so that the user can use a toggle/switch to change between two units for the entire app, specifically "metric tons" and "short tons". While the actual conversion functions are provided within a dedicated

问题 I have a component which triggers an onScrollEnd event when the last item in a virtual list is rendered. This event will do a new API request to fetch the next page and merge them with the previous results using the scan operator. This component also has a search field which triggers an onSearch event. How do I clear the previous accumulated results from the scan operator when a search event is triggered? Or do I need to refactor my logic here? const loading$ = new BehaviorSubject(false);

问题 I have a component which triggers an onScrollEnd event when the last item in a virtual list is rendered. This event will do a new API request to fetch the next page and merge them with the previous results using the scan operator. This component also has a search field which triggers an onSearch event. How do I clear the previous accumulated results from the scan operator when a search event is triggered? Or do I need to refactor my logic here? const loading$ = new BehaviorSubject(false);

问题 A very common problem when using RxJs seems to be to want the result of one or more observables to then use them in subsequent ones. e.g. in pseudo-code (This is not rx or valid js syntax deliberately) var someResult = $observable-A; // wait to complete var finalResult = $observable-B(someResult.aValueINeed); This can be done in an ugly way where you could subscribe to both and call one inside the other.. however, this is very messy and doesn't afford you much flexibility. e.g. (real syntax)

问题 I'm trying to understand throttleTime vs debounceTime and which one is to be used when? I have an upvote button that makes an API request to the backend (which counts the votes). User can submit button multiple times, but I'd like to limit the times per second button can be pressed. I know throttleTime and debounceTime operators can do that, but which should I choose better? const upvoteClicks = fromEvent(this.el.nativeElement, 'click') .pipe(debounceTime(500)) .subscribe(() => this.myService

问题 I am looking for an operator that would help me pace the results emitted from an observable, it would look like this : [--A-BC--D-E----------------] [--A----B----C----D----E----] I tried AuditTime() but it does not replay the results that was emitted between intervals, it does something like this : [--A-BC--D-E----------------] [--A----C----E--------------] Thanks for your help. 回答1: I think this should do what you need: const e1 = cold('--A-BC--D-E----------------|'); const expected = '--A--

问题 I'm using rxjs with NodeJS in backend. I have a Rest API which allow consumers to run remote yarn installation process. The install function returns an observable of the process. So when the module is installed successfully it emits a value in the observable and complete. At this point, the Rest API will returns a response to the user to say that the installation is successful. In case that the installation fails, the process will throw an Error in the stream and the Rest API returns another