使用 AngularFireObject 和 switchMap [英] Working with AngularFireObject and switchMap

问题描述

我真的不知道如何解决这个问题.如何修复此错误?

 在 user.service.ts 中:从'@angular/core'导入{可注射}；从 'angularfire2/database' 导入 { AngularFireDatabase, AngularFireList, AngularFireObject };从'./models/app.user'导入{AppUser}；从'firebase'导入*作为firebase；从 'rxjs' 导入 { Observable };@Injectable({提供在:'根'})导出类 UserService {构造函数(私有数据库:AngularFireDatabase){}保存(用户:firebase.User){this.db.object('/users/' + user.uid).update({名称:user.displayName，电子邮件:user.email});}get(uid: string): AngularFireObject{return this.db.object('/users/' + uid);}在 admin-auth-guard.service 中:从'@angular/core'导入{可注射}；从 'rxjs/observable' 导入 { Observable };导入 'rxjs/add/operator/switchMap';导入 'rxjs/operator/map';从 './user.service' 导入 { UserService };从'@angular/router'导入{CanActivate}；从 './auth.service' 导入 { AuthService };@Injectable({提供在:'根'})导出类 AdminAuthGuard {构造函数(私有身份验证:AuthService，私有用户服务:UserService){}canActivate(): Observable{返回 this.auth.user$.switchMap(user => this.userService.get(user.uid))<-- 错误在这里.map (appUser => appUser.isAdmin);}}

<块引用>

'(user: User) => AngularFireObject' 类型的参数不是可分配给类型为 '(value: User, index: number) => 的参数ObservableInput<{}>'.类型 'AngularFireObject' 不是可分配到类型ObservableInput<{}>".类型AngularFireObject"不可分配给类型Iterable<{}>".AngularFireObject"类型中缺少属性[Symbol.iterator]".

谢谢.

解决方案

在 Angular 6 中这样做:

user.service.ts:从'@angular/core'导入{可注射}；从 'angularfire2/database' 导入 { AngularFireDatabase, AngularFireObject };从'./models/app.user'导入{AppUser}；从'firebase'导入*作为firebase；从 'rxjs' 导入 { Observable };@Injectable({提供在:'根'})导出类 UserService {构造函数(私有数据库:AngularFireDatabase){}保存(用户:firebase.User){this.db.object('/users/' + user.uid).update({名称:user.displayName，电子邮件:user.email});}get(uid: string): AngularFireObject{return this.db.object('/users/' + uid);}}在 admin-auth-guard.service.ts 中:从 './user.service' 导入 { UserService };从 'rxjs/operators' 导入 { map, switchMap };从 './auth.service' 导入 { AuthService };从'@angular/core'导入{可注射}；从'@angular/router'导入{CanActivate}；从 'rxjs' 导入 { Observable };@Injectable({提供在:'根'})导出类 AdminAuthGuard 实现 CanActivate {构造函数(私有身份验证:AuthService，私有用户服务:UserService){}canActivate(): Observable{返回 this.auth.user$.pipe(switchMap(user => this.userService.get(user.uid).valueChanges())).pipe(map(appUser => appUser.isAdmin));}}

I really don't know how to fix this. How can I fix this error?

in user.service.ts:
import { Injectable } from '@angular/core';

import { AngularFireDatabase, AngularFireList, AngularFireObject } from 'angularfire2/database';

import {AppUser} from './models/app.user';
import * as firebase from 'firebase';
import { Observable } from 'rxjs';

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


  constructor(private db: AngularFireDatabase) { }

  save(user: firebase.User) {
    this.db.object('/users/' + user.uid).update({
      name: user.displayName,
      email: user.email
    });
  }

  get(uid: string): AngularFireObject<AppUser> {
    return this.db.object('/users/' + uid);
  }



in admin-auth-guard.service:

import { Injectable } from '@angular/core';
import { Observable } from 'rxjs/observable';
import 'rxjs/add/operator/switchMap';
import 'rxjs/operator/map';
import { UserService } from './user.service';
import { CanActivate } from '@angular/router';
import { AuthService } from './auth.service';



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

  constructor(private auth: AuthService, private userService: UserService) { }

   canActivate (): Observable<boolean> {
     return this.auth.user$
      .switchMap(user => this.userService.get(user.uid))<-- ERROR HERE
      .map (appUser => appUser.isAdmin);
    }
}

Argument of type '(user: User) => AngularFireObject' is not assignable to parameter of type '(value: User, index: number) => ObservableInput<{}>'. Type 'AngularFireObject' is not assignable to type 'ObservableInput<{}>'. Type 'AngularFireObject' is not assignable to type 'Iterable<{}>'. Property '[Symbol.iterator]' is missing in type 'AngularFireObject'.

Thanks.

解决方案

Do it this way for Angular 6:

user.service.ts:

import { Injectable } from '@angular/core';

import { AngularFireDatabase, AngularFireObject } from 'angularfire2/database';

import {AppUser} from './models/app.user';
import * as firebase from 'firebase';
import { Observable } from 'rxjs';

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


  constructor(private db: AngularFireDatabase) { }

  save(user: firebase.User) {
    this.db.object('/users/' + user.uid).update({
      name: user.displayName,
      email: user.email
    });
  }

  get(uid: string): AngularFireObject<AppUser> {
      return this.db.object('/users/' + uid);
  }

}



In admin-auth-guard.service.ts:


import { UserService } from './user.service';
import { map, switchMap } from 'rxjs/operators';
import { AuthService } from './auth.service';
import { Injectable } from '@angular/core';
import { CanActivate } from '@angular/router';
import { Observable } from 'rxjs';

@Injectable({
  providedIn: 'root'
})
export class AdminAuthGuard implements CanActivate {

  constructor(private auth: AuthService, private userService: UserService) { }

  canActivate(): Observable<boolean> {
    return this.auth.user$
    .pipe(switchMap(user => this.userService.get(user.uid).valueChanges()))
    .pipe(map(appUser => appUser.isAdmin));
   }

}

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