getCampaigns(): Observable<Campaign[]> {
    return this.http.get('/campaigns').map(res => res.json());
}

假设服务器返回401.如何在全局范围内捕获此错误并重定向到登录页面/组件？

谢谢。

这里是我到目前为止：

// boot.ts

import {Http,XHRBackend,RequestOptions} from 'angular2/http';
import {CustomHttp} from './customhttp';

bootstrap(AppComponent,[HTTP_PROVIDERS,ROUTER_PROVIDERS,new Provider(Http,{
        useFactory: (backend: XHRBackend,defaultOptions: RequestOptions) => new CustomHttp(backend,defaultOptions),deps: [XHRBackend,RequestOptions]
    })
]);

// customhttp.ts

import {Http,ConnectionBackend,Request,RequestOptions,RequestOptionsArgs,Response} from 'angular2/http';
import {Observable} from 'rxjs/Observable';

@Injectable()
export class CustomHttp extends Http {
    constructor(backend: ConnectionBackend,defaultOptions: RequestOptions) {
        super(backend,defaultOptions);
    }

    request(url: string | Request,options?: RequestOptionsArgs): Observable<Response> {

        console.log('request...');

        return super.request(url,options);        
    }

    get(url: string,options?: RequestOptionsArgs): Observable<Response> {

        console.log('get...');

        return super.get(url,options);
    }
}

我得到的错误信息是“backend.createConnection不是一个功能”