Question

我正在尝试从http.get访问WEB API但它无法正常工作这是我使用observable的服务，但它根本不工作既不调用服务器也不显示任何错误好。

@Injectable()
export class SetupServiceObservables {

    public apiServiceBaseUri = 'http://localhost:3000/';

    private authheaders: any = {};
    private config: any = {};
    private auth: any = {};

    constructor(private http: Http, private ngWEBAPISettings: WebAPISettings, private authService: AuthService, private router: Router) {

    }

    public get(servicename: string): Observable<any> {
        return this.http.get(this.ngWEBAPISettings.apiServiceBaseUri + "api/" + servicename + "/", this.getConfig())
            .map(this.extractData)
            .catch(this.handleError);;
    }

    public getConfig() {
        this.authheaders.Authorization = this.auth.access_token == "" ? "" : 'Bearer ' + this.auth.access_token;
        this.config = {
            headers: {
                'Authorization': this.authheaders.Authorization
            },
            cache: false,
        };
        return this.config;
    }



    private extractData(res: Response) {
        let body = res.json();
        console.log(res);
        return body.data || {};
    }


    private handleError(error: any) {
        let errMsg = (error.message) ? error.message :
            error.status ? `${error.status} - ${error.statusText}` : 'Server error';
        console.error(errMsg); // log to console instead
        return Observable.throw(errMsg);
    }
}

Answer 1

Observable很冷，所以你必须致电subscribe

示例服务实现如下所示 -

 getEmployees(): Observable<{}> {
        return this._http.get(this._webApiUrl)
            .map((response: Response) => <any[]> response.json())
             .catch(this.handleError)
            ;
    }

您可以从您的组件订阅 -

 this._webApiService.getEmployees().subscribe(
                emplist => this.employees = emplist,
                error => this.errorMessage = <any>error
                );

看看这是否有帮助。

在webapi上观察不到角2

1 个答案: