Question

我正在使用Angular和firebase构建应用程序（使用AngularFire2）。当尝试在任何firebase observable（FirebaseAuthObservable，FirebaseListObservable）上使用.map运算符时，我收到错误

[s] Supplied parameters do not match any signature of call target. (property) AngularFire.auth: AngularFireAuth

这是我的代码

import { Component, OnInit } from '@angular/core';
import { AngularFire } from 'angularfire2'
import { Router, ActivatedRoute } from '@angular/router';
import {Observable } from 'rxjs/Observable';
import 'rxjs/Rx';

@Component({
  selector: 'app-edit-objective',
  templateUrl: './edit-objective.component.html',
  styleUrls: ['./edit-objective.component.css']
})
export class EditObjectiveComponent implements OnInit {

    constructor(private af: AngularFire, private route: ActivatedRoute, public router: Router) { }

    ngOnInit() {
        this.af.auth
         .map((x) => {})
         .subscribe(y => console.log(y))
    }
}

这里有什么我想念的吗？

编辑**

我尝试过创建一个新的Observable并在其上使用map运算符，但这也无效。

import { Component } from '@angular/core';
import {Observable} from 'rxjs/Observable';
import 'rxjs/add/operator/map';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent {
  constructor() {
    let x: Observable<string> = Observable.create(observer => {
      observer.next('test');
    })
    x.map(str => str + " ");  //Error on this line (see below)
  }
}

我得到的错误是：

[ts] Supplied parameters do not match any signature of call target.
pplies a given project function to each value emitted by the source
Observable, and emits the resulting values as an Observable.

<span class="informal">Like Array.prototype.map(),
it passes each source value through a transformation function to get
corresponding output values.</span>

<img src="./img/map.png" width="100%">

Similar to the well known Array.prototype.map function, this operator
applies a projection to each value and emits that projection in the output
Observable.

@example <caption>Map every click to the clientX position of that click</caption>
var clicks = Rx.Observable.fromEvent(document, 'click');
var positions = clicks.map(ev => ev.clientX);
positions.subscribe(x => console.log(x));

@see {@link mapTo}
@see {@link pluck}

@return {Observable<R>} An Observable that emits the values from the source
Observable transformed by the given project function.
@method map
@owner Observable

Answer 1

您没有导入AngularFireAuth（以前称为FirebaseAuth）

equals

map运算符不能处理AngularFireAuth Observable

1 个答案: