Question

我在我的angular2应用程序中有一个名为HttpClient的服务。此服务应该为应用程序发送到我的终端的每个请求添加一个授权标头。

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

import { Router } from '@angular/router';

import { ErrorService } from '../../services/error/error.service'

@Injectable()
export class HttpClient {

    private token: string;
    private error: any;

    private webApi = 'http://localhost:8080/api/v1/';    // Url to web api

    constructor(
        private http: Http,
        private router: Router,
        private errorService: ErrorService) { }

    get(url: string): Promise<Response> {
        return this.http.get(this.webApi + url, this.createAuthorizationHeader())
                    .toPromise()
                    .catch((e) => this.handleError(e));
    }

    post(url: string, data: any): Promise<Response> {
        return this.http.post(this.webApi + url, JSON.stringify(data), this.createAuthorizationHeader())
                    .toPromise()
                    .catch((e) => this.handleError(e));
    }

    put(url: string): Promise<Response> {
        return this.http.get(this.webApi + url, this.createAuthorizationHeader())
                    .toPromise()
                    .catch((e) => this.handleError(e));
    }

    delete(url: string): Promise<Response> {
        return this.http.delete(this.webApi + url, this.createAuthorizationHeader())
                    .toPromise()
                    .catch((e) => this.handleError(e));
    }

    private handleError (error: any) {

        var status: number = error.status;

        if (status == 415) {
            this.errorService.setError(error);
        }

        let errMsg = (error.message)
            ? error.message
            : status
                ? `${status} - ${error.statusText}`
                : 'Server error';

        console.error(errMsg); // log to console instead
        return Promise.reject(errMsg);
    }

    private createAuthorizationHeader() {

        let headers = new Headers();
        headers.append('Content-Type', 'application/json');
        headers.append('Accept', 'application/json');

        if (localStorage.getItem('token'))
            this.token = localStorage.getItem('token');

        headers.append('Authorization', 'Bearer ' + this.token);

        return headers;
    }
}

此服务还将错误设置为另一个名为ErrorService

的自定义服务

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

@Injectable()
export class ErrorService {

    error: any;

    public errorAdded$: EventEmitter<any>;

    constructor() {
        this.errorAdded$ = new EventEmitter();
    }

    getError(): any {
        return this.error;
    }

    setError(error: any) {
        alert('is not going to be called');
        this.error.error = error;
        this.errorAdded$.emit(error);
    }
}

这些服务将在我的main.ts中自行启动

...
import { ErrorService }   from './services/error/error.service';
import { HttpClient }   from './services/http/http.service';
...

bootstrap(AppComponent, [
    appRouterProviders,
    HTTP_PROVIDERS,
    ErrorService,
    HttpClient,
    ....
]);

现在我想在我的标题组件中显示此错误。因此超时发生错误，此错误将显示在我标题中的单独框中。

问题是ErrorService.setError(error)中调用的HttpClient.handleError方法甚至无法解雇。

Answer 1

.catch(this.handleError);

应该是

.catch((e) => this.handleError(e));

保留this.的范围其中(e)是参数列表

或者你可以使用

.catch(this.handleError.bind(this));

Angular2 - 无法提供可注射服务

1 个答案: