angular 2 http withCredentials

I'm am trying to use withCredentials to send a cookie along to my service but can't find out how to implement it. The docs say "If the server requires user credentials, we'll enable them in the request headers" With no examples. I have tried several different ways but it still will not send my cookie. Here is my code so far.

private systemConnect(token) {
    let headers = new Headers();
    headers.append('Content-Type', 'application/json');
    headers.append('X-CSRF-Token', token.token);
    let options = new RequestOptions({ headers: headers });
    this.http.post(this.connectUrl, { withCredentials: true }, options).map(res => res.json())
    .subscribe(uid => {
        console.log(uid);
    });
}

Try to change your code like this

let options = new RequestOptions({ headers: headers, withCredentials: true });

and

this.http.post(this.connectUrl, <stringified_data> , options)...

as you see, the second param should be data to send (using JSON.stringify or just '') and all options in one third parameter.

Starting with Angular 4.3, HttpClient and Interceptors were introduced.

A quick example is shown below:

@Injectable()
export class WithCredentialsInterceptor implements HttpInterceptor {

    intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {

        request = request.clone({
            withCredentials: true
        });

        return next.handle(request);
    }
}

constructor(
      private http: HttpClient) {

this.http.get<WeatherForecast[]>('api/SampleData/WeatherForecasts')
    .subscribe(result => {
        this.forecasts = result;
    },
    error => {
        console.error(error);
    });

Remember to provide the interceptor to your app module, as the article says:

In order to activate the interceptor for our application we need to provide it to the main application module AppModule in file app.module.ts:

Your @NgModule will need to include this in its providers:

  ...
  providers: [{
    provide: HTTP_INTERCEPTORS,
    useClass: WithCredentialsInterceptor,
    multi: true
  }],
  ...