angular - 类型 'toPromise' 上不存在属性 'Observable<Response>'

Question

import { Headers, Http } from '@angular/http';

@Injectable()
export class PublisherService{

    private publishersUrl = 'app/publisher';

    constructor(private http: Http) { }

    getPublishers(): Promise<Publisher[]>{
        return this.http.get(this.publishersUrl)
                   .toPromise()
                   .then(response => response.json().data) 
                   .catch(this.handleError);
    }
}    

我收到这个错误:

Property 'toPromise' does not exist on type 'Observable'.any

Answer 1

您需要像这样添加运算符:

import 'rxjs/add/operator/toPromise';

这是您要使用的每个 rxjs 运算符所必需的。