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TS2339:类型“Object”上不存在属性“map”

ionic3 ionic-framework typescript angular

0

Drago · 技术社区 · 6 年前

我有以下代码:

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { Observable } from 'rxjs/Observable';
import 'rxjs/add/operator/catch';
import { map } from 'rxjs/operators';

interface SingleParamConstructor<T> {
  new (response: any): T;
  id: T;
}

@Injectable()
export class RestProvider<T> {
  baseUrl:string = "http://localhost:3000";

  constructor(private ctor: SingleParamConstructor<T>, private httpClient : HttpClient) { }

  public getEntities<T>(): Observable<T[]> {
    return this.httpClient
      .get(this.baseUrl + '/products')
      .pipe(map(entities => {
        return entities.map((entity) => new this.ctor(entity));
      }))
      .catch((err) => Observable.throw(err));

  }
}

当我尝试上面的代码时,我得到了 TS2339: Property 'map' does not exist on type 'Object'

责任线是: return entities.map((entity) => new this.ctor(entity));

我做错了什么?我该怎么做 entities ?

1 回复 | 直到 6 年前

1

2

AT82 6 年前

你不是在讲故事 get ,所以Angular会自动假定它是 an anonymous object, as that is what Angular httpclient parses to the data to . 还有一些不相关的东西,因为您使用的是rxjs 6->使用 catchError 而不是 .catch

import { catchError, map } from 'rxjs/operators';
import { of } from 'rxjs';

// ...

public getEntities<T>(): Observable<T[]> {
  return this.httpClient
    // note below, now angular knows it's an array!
    .get<T[]>(this.baseUrl + '/products')
    .pipe(
       map(entities => {
        return entities.map((entity) => new this.ctor(entity));
       }),
       catchError((err) => of(err))
    )
}

2

1

Francisco Santorelli 6 年前

我几乎可以肯定( entities

更改 pipe(map 到 pipe(tap 并执行console.log以查看您从服务器获得的信息,

.pipe(tap(entities => console.log(entities));

希望这对你有帮助