小编Ash*_*uti的帖子

我做了错误处理程序代码，但我在 catch 中出错了。未定义的方法。

这是我的 serivce.ts 代码。

import { Injectable } from "@angular/core";
import { HttpClient, HttpErrorResponse } from "@angular/common/http";
import { user } from "./user";
import { Observable } from "rxjs";
import "rxjs/add/operator/catch";
import "rxjs/add/Observable/throw";
@Injectable({
  providedIn: "root"
})
export class DemoService {
  private url: string = "/assets/demo/user.json";
  constructor(private http: HttpClient) {}

  getuserdetails(): Observable<user[]> {
    return this.http.get<user[]>(this.url).catch(this.errorHandler);
  }
  errorHandler(error: HttpErrorResponse) {
    return Observable.throw(error.message || "server error.");
  }
}

这是我的 app.component.ts 文件代码

 public userdetails = [];
  public errorMsg;
  constructor(private user: DemoService) …