Angular 9 вызов веб-службы возвращает isScaler = false, но нет данных - PullRequest
Новая
       16

Angular 9 вызов веб-службы возвращает isScaler = false, но нет данных

0 голосов
/ 27 мая 2020

mysurveys.service.ts 

import { Injectable } from '@angular/core';
import { HttpClient  } from '@angular/common/http';
import { Observable } from 'rxjs';

@Injectable({
  providedIn: 'root'
})
export class MyserviceService {

  constructor(private http:HttpClient) { }
  getSurveys(): Observable<isurvey[]>{
    var url = 'http://localhost/serversideapp/index';
    return this.http.get<isurvey[]>(url);
  } 
}

export interface isurvey{
  id: string;
  title: string;
}

app.component.ts 

import { Component,OnInit } from '@angular/core';
import { MyserviceService } from './myservice.service';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.scss']
})
export class AppComponent implements OnInit{
  public surveys:any = [];
  constructor(private surveySrv:MyserviceService){}

  ngOnInit(){
    this.surveys =this.surveySrv.getSurveys();
  }
}

app.component. html

<div class="survey" *ngFor="let survey of surveys">
  <h1>{{survey.id}}</h1>
  <p>{{survey.title}}</p>
</div>  
<p>{{surveys | json}}</p>

возвращается следующее

{ "_isScalar": false, "source": { "_isScalar": false, "source": { "_isScalar": false, "source": { "_isScalar": false }, "operator": { "concurrent": 1 } }, "operator": {} }, "operator": {} }

с сообщением об ошибке в консоли, как показано ниже 

ERROR Error: Cannot find a differ supporting object '[object Object]' of type 'object'. NgFor only supports binding to Iterables such as Arrays.
    at NgForOf.ngDoCheck (common.js:4406)
    at callHook (core.js:4730)
    at callHooks (core.js:4690)
    at executeInitAndCheckHooks (core.js:4630)
    at selectIndexInternal (core.js:9748)
    at Module.ɵɵadvance (core.js:9709)
    at AppComponent_Template (app.component.html:6)
    at executeTemplate (core.js:12156)
    at refreshView (core.js:11995)
    at refreshComponent (core.js:13445)
...