如何从angular2 firebase数据中获取数据。

Question

我有angular2 firebase中的candidates_list表，但我没有从中获取值。

我的TS文件是这样的

import { Component, OnInit,Input } from '@angular/core'; 
import { AngularFireDatabase, FirebaseListObservable, FirebaseObjectObservable } from 'angularfire2/database'; 
import * as firebase from 'firebase'; 
import { FirebseService } from "app/firebse.service"; 

@Component({ 
    selector: 'app-candidate-reg-complete', 
    templateUrl: './candidate-reg-complete.component.html', 
    styleUrls: ['./candidate-reg-complete.component.css'] 
}) 
export class CandidateRegCompleteComponent implements OnInit { 
    content:any; 
item: FirebaseObjectObservable<any>; 
    constructor(private db: AngularFireDatabase, 
    private firebaseService:FirebseService) { 
    this.item = db.object('candidates_list'); 
    } 

    ngOnInit() { 
    } 
    upload(documents){ 

    // let file=user.files[0]; 
    // console.log(file); 
    // console.log(file.name); 
    let storageRef=firebase.storage().ref(); 

    for(let selectedFile of[(<HTMLInputElement>document.getElementById('file')).files[0]]){ 

    let path='/resumes/'+selectedFile.name; 
     let iRef=storageRef.child(path); 
     iRef.put(selectedFile).then((snapshot)=>{ 
     debugger; 
     documents.resume=selectedFile.name; 
     documents.path=path; 

     var Userid=localStorage.getItem('user'); 
     console.log(documents); 
     let content=this.db.object('/candidates_list/'+Userid); 
     console.log(content); 

     // this.db.object('/candidates_list/'+Userid).update(documents); 
     localStorage.setItem('resume',documents.path); 

     }) 
} 

} 
} 

问题是这段代码

let content=this.db.object('/candidates_list/'+Userid); 
console.log(content); 

当我试图安慰这个值时，输出是这样的..

FirebaseObjectObservable {_isScalar: false, $ref: U, source: FirebaseObjectObservable, operator: ObserveOnOperator} 

不赞成确切的内容，所以这个问题的任何解决方案？

Answer 1

您需要订阅observable。试试这个：

let content = this.db.object('/candidates_list/'+Userid) 
    content.subscribe(data => { 
    console.log(data)})