我正在构建一个angular 2服务来搜索特定信息。我的服务几乎可以正常使用,但是我不断收到此错误消息:core.es5.js:1020 ERROR TypeError: res.json is not a function at MapSubscriber.project
import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { Response } from '@angular/http';
import { Observable } from 'rxjs/Observable';
import 'rxjs/add/operator/map';
import 'rxjs/add/operator/debounceTime';
import 'rxjs/add/operator/distinctUntilChanged';
import 'rxjs/add/operator/switchMap';
import { FundraiserProgressService } from 'app/services/fundraiser-progress.service';
@Injectable()
export class SearchService {
baseUrl: String = 'http://localhost:4402/items';
queryUrl: string = '?search=';
constructor(private http: HttpClient) { }
search(terms: Observable<string>) {
return terms.debounceTime(400)
.distinctUntilChanged()
.switchMap(term => this.searchEntries(term));
}
searchEntries(term) {
return this.http
.get(this.baseUrl + this.queryUrl + term)
.map((res: Response) => res.json())
}
}
最佳答案
这是因为在Angular版本4.3.0中使用新的HttpClient
时,JSON是假定的默认值,不再需要显式解析。因此,您可以删除.map((res: Response) => res.json())
。
这是取自documentation的示例:
@Component(...)
export class MyComponent implements OnInit {
results: string[];
// Inject HttpClient into your component or service.
constructor(private http: HttpClient) {}
ngOnInit(): void {
// Make the HTTP request:
this.http.get('/api/items').subscribe(data => {
// Read the result field from the JSON response.
this.results = data['results'];
});
}
}