ERROR TypeError: Converting circular structure to JSON --> starting at object with constructor 'FirebaseAppImpl' Firebase Angular

Question

当尝试从可观察对象获取数据时，我从控制台收到此错误。

我的代码如下

Anglar 服务 - service.ts

     import { Injectable } from '@angular/core';
        import { AngularFirestore } from '@angular/fire/firestore';
        @Injectable({
          providedIn: 'root'
        })
        export class ViewReportService {
          constructor(private firestore: AngularFirestore) { }
          getReport = (myDocument) => 
            this.firestore.collection("report").doc(myDocument).get()
        }

组件 ts.

  import { Component, OnInit } from '@angular/core';
    import { ViewReportService } from '../shared/view-report.service';
    import { Observable } from 'rxjs';
    @Component({
      selector: 'app-view-report',
      templateUrl: './view-report.component.html',
      styleUrls: ['./view-report.component.scss']
    })
    export class ViewReportComponent implements OnInit {
      document= [];
      document$ : Observable<any>;
      constructor(private service: ViewReportService) { }
      ngOnInit(){
        let documentID = "----"
        //Get the Data from the view-report service
        this.document$ = this.service.getReport(documentID);
      }
    }

在我的 HTML 视图中

 <table *ngIf="document$ | async as document">
        <pre>{{document.name}}</pre>

Answer 1

听起来你有一个循环对象结构，然后不能存储在数据库中。请记住：Firestore 文档只能包含 JSON 数据，并非所有 JavaScript 对象都是有效的 JSON。例如：JavaScript 对象可能包含函数定义，这些定义在 JSON.

中无效

将 JavaScript 对象转换为 JSON 的最简单方法是 JSON.parse(JSON.stringify(object))。您需要在将对象写入数据库的地方执行此操作。

ERROR TypeError: Converting circular structure to JSON --> starting at object with constructor 'FirebaseAppImpl' Firebase Angular

ERROR TypeError: Converting circular structure to JSON --> starting at object with constructor 'FirebaseAppImpl' Firebase Angular

javascript

firebase

angularfire2

angular

google-cloud-firestore