rxjs

问题 I have a service that is used to upload pictures. To upload a picture, all I do is return this.http.post(/* ... */) And I get a subscription I can subscribe to in my component. But when I want to upload several pictures, I have to do for (let p of pics) { this.http.post(/* ... */); } My problem is that I would like to return the results of all calls instead of just one call. Is that possible ? EDIT Here is my service addPictures(files: File[], folder: string): Observable<Parse.Object[]> { let

问题 I am trying to get distinct values of a property in an observable array. let pt$ = Observable.of([{planTypeID : 1, description : 'test 1'}, {planTypeID : 2, description : 'test 2'}]); let planTypeIDs$ = pt$ .flatMap(a => a) .map(a => a.planTypeID).distinct().toArray(); Is this the right way to do it in rxjs, or is there a better way? 回答1: You could use .from instead of .of , that should spare you the .flatMap distinct will check the reference by default, so if you want to compare for contents

问题 I want to bind a parent component input element value to a child component property. The wrinkle is that the child component is nested within the parent via router-outlet. It seems like the best approach is to use a shared service between the parent and child component as demonstrated here. Here's my testing implementation: Parent component : import { Component } from '@angular/core'; import { Router } from '@angular/router'; import { ThreadsService } from './threads.service'; @Component({

问题 I am trying a use case of reading a json file asynchronously and sending it out as a response (as a rxjs observable data). Here is the service that I use import { logger } from './../../shared/utils/logger'; import { Injectable } from '@nestjs/common'; import * as fs from 'fs'; import * as path from 'path'; import { BehaviorSubject, Observable, pipe, of, from, throwError, merge} from 'rxjs'; import { map, filter, scan, take, debounce, switchMap, retry, catchError, mergeMap, delay, zip, tap,

问题 I am able to translate text using translate pipe but currently struggling to load translations using translate service's get and instant method. Below is my code in app.component.ts export class AppComponent { event : string; constructor(private translate: TranslateService) { translate.addLangs(["en", "fr"]); translate.setDefaultLang('en'); let LangChangeEvent : {} let browserLang = translate.getBrowserLang(); translate.use(browserLang.match(/en|fr/) ? browserLang : 'en'); this.translate.get(

问题 Before each request a HTTP interceptor checks if the access token is expired and if so, it first renews the token and then continues the request. The problem is on pages that have multiple requests. On those pages the interceptor tries to renew the token for each request. How can I share the token renewal request in this case? The method that is responsible for token renewal is this: renewToken() { let refreshToken = // get refresh token let accessToken = // get access token if (!refreshToken

问题 I am getting the following error which shows up in IE/Edge only. Unable to get propety '0' of undefined or null reference I am using RxJs observables in the following manner: getVersions(): void { this.databaseService.getProductVersions().subscribe( (versions) => this.processVersions(versions), (error) => console.error(error) ); } and in Chrome/Firefox this works without errors. productVersions looks like this: getProductVersions(): Observable<any[]> { let options = this.header(); let url:

问题 I have a method getData() inside Angular app which calls on click every time when asc > desc sorting in the table is changed. If I click it 10 times in a row I will make 10 get request and data will assign to table every time when the request is resolved, so it makes it blinking till the last request. How can I waiting for data only for the last request and ignore another? this.getData() { this.endpointsService.getData(reqParams).pipe( takeUntil(this.ngUnsubscribe$) ).subscribe((data) => {

问题 Here a quite complex sample: Main: this.runInstructionAndGetResult().subscribe({ next: val => console.log(`NEXT VALUE: ${val}`), error: val => console.log(`ERROR VALUE: ${val}`), complete: val => console.log(`COMPLETE`) }); Observables: public runInstructionAndGetResult(): Observable<string> { return this.runAnInstruction() .flatMap((data) => { console.info("flatMap of runAnInstruction:", data); return this.getInstructionExecutionStatusInPolling() .filter(data => data != "Polling") .take(1)

问题 Consider I have 3 components. 1. PatientComponent in /patient 2.PatientListComponent in /patient/list 3.PatientCareXComponent in /patient/care/x I used behaviorsubject in patient.service.ts to cast the data from patientlistcomponent. I face some issues: 1. Initially in /patient/list page from where data arrives, I see data visible in PatientComponent in console.logs but not PatientCareXComponent. 2. When i move to /patient page from /patient/list, the visible data also disappears. The code is