private extractData(res: Response) {
     let body = res.json();
     return new Task(body.jobItemId, body.code, body.jsonData);
 }

 private handleError(error:Response) {
   let _error = error.json();
   console.error(_error);
   toastr.error(_error.message);
   return Observable.throw(_error.error || 'Server error');
 }

 handleErrors(error: Response) {
     return Observable.throw(error.json().error || 'Server error');
 }

	protected extractData(res: Response){
		let body = res.json();
		return body || { };
	}

			.subscribe((res: Response) => {
				cb(res.json());		//callBack
			});

 this.particleService.getVariable(device.id, sensor).subscribe((res: Response) => {
     var sensorResponse = res.json();
     device.variables[sensorResponse.name] = sensorResponse.result;
 });

    public handleResponseError(error:Response){

        console.error(error);
        return Observable.throw(error.json().error || 'Server error');
    }

 .map((res: Response) => {
   return BlogEntry.asBlogEntries(res.json());
 }, this.getOptions());

 json (res: Response) {
     let body = res.json();
     return body || {};
 }