subject

问题 Why Event Emitter can't use in service in angular 6? In Angular documentation they mentioned, "Use in directives and components to emit custom events" 回答1: Because in services all waht you have to do is manipulating data, if you want to notify the data changes you can use Subjet or BehaviorSubjet . EventEmitter is generally used to notify changes from child to parent and as said is supposed to be used only for @Output . please take a look at this link 来源： https://stackoverflow.com/questions

问题 How to invoke a method when all the observers have unsubscribed from a subject. Update const alphaStore = new BehaviourSubject(0); observer1 = alphaStore.subscribe(console.log); observer2 = alphaStore.subscribe(console.log); And when all of these observers unsubscribe. I want a method to be invoked. Like... Observer1 unsubscribed Observer2 unsubscribed All observers left 回答1: What you describe already does the finalize() operator. Better said finalize() calls its callback when the chain

来源： https://stackoverflow.com/questions/63354585/how-to-send-to-a-subject-different-observable-results-without-having-to-break-th

问题 I have an application where many of our endpoints do not support DNS lookups so for those endpoints they cannot use a URL to hit our servers. Our application gives out a list of IPs of our servers they need to hit and this works fine for http. I am trying to enable use of https to hit our servers and I have created a SAN cert with some urls as Subject Alternative Names plus the IPs of our servers as Subject Alternative names. For example in the openssl.cnf I used to create the CSR I have: DNS

问题 So I keep reading everywhere that use of Subject<T> is "bad" - and I kind of agree with the reasoning. However, I am trying to think of the best way to avoid using it and have an example. Currently I have an abstract class for my persisted configuration classes that has a protected Save() method on it which is called whenever changing a property should persist the class. This message pumps a message onto a Subject<T> which is exposed through IObservable<T> interface which the serialisation

问题 How can I insert line breaks inside HTML attribute values, like this: <href="mailto:info@example.com?subject=TestMail&body=Please enter the following details. Name Email Mob No"> When the user replies, the body part should display as below: Please enter the following details. 1. Name 2. Email 3. Mob No I tried using <br> tags, but they get displayed. 回答1: The line break should be URL encoded into %0D%0A Your mailto will look like: <a href="mailto:xxx@example.com?subject&body=1.Name%0D%0A2

问题 I am receiving data from firebase server in chunks while rendering that data requires a library which insists on observable contains Array. I am somehow unable to push a new data chunk to existing data chunk array contained by observable, From dataservice I am calling by subject's next and trying to add a new calEvent this.homeWorkerService.eventSubject.next(calEvent); In component, I have following code events$: Observable<Array<CalendarEvent<any>>>; and ngOnInit, I am supplying data to it

问题 I need to trigger Host listeners after a click of a certain button. The host listeners should then highlight any hovered element on page and listen to mouse clicks which would open a modal. Problem is that when I start listening for mouse clicks and do click, the modal sometimes doesn't open until I click the button that triggers the Host listeners. Also the highlighted elements get 'stuck' and stay highlighted after a mouse click trying to open a modal. Is it an asynchronous problem? Any

问题 I need to trigger Host listeners after a click of a certain button. The host listeners should then highlight any hovered element on page and listen to mouse clicks which would open a modal. Problem is that when I start listening for mouse clicks and do click, the modal sometimes doesn't open until I click the button that triggers the Host listeners. Also the highlighted elements get 'stuck' and stay highlighted after a mouse click trying to open a modal. Is it an asynchronous problem? Any

问题 I have an API which exposes an IObservable Status. But this status depends on an underlying observable source which has to be initialised via Init . What I'd like to do is protect the users from having to do things in the right order: as it currently stands, if they try to subscribe to the Status before performing an Init , they get an exception because they source is not initialised. So I had the genius idea of using a Subject to decouple the two: the external user subscribing to my Status