I have a question about the `Observable` parameter, in my case, i have a consultService who has the functions `consult()` and the parameter response. The `sendConsultRequest()` function is called before using the parameter response. The sendConsultRequest works just fine because i can see the result in the page, but when i want to export the content by using the parameter response, i have the problem:

> 
> **ERROR TypeError: Cannot read property 'dataList' of undefined**
> 
> 
> 

In my opnion, the response parameter is already initialized before the export action, because the consultPage works good.
Here is the service code, can you show me why it doesn't work, please?

```
@Injectable()
export class ConsultService {
  private url = 'api/consultApplication';
  response: Application;

sendConsultRequest(id: string) {
  console.log('sendConsultRequest');
  this.http.get<Application[]>(this.url)
    .subscribe(response => {
      response.map(res => {
        this.response = res;
        this.updateApplication(res);
      }),
        pipe(catchError(this.handleError('sendConsultRequest', [])));
    });
}

```

Here is the export page ts:

```
ngOnInit() {
  console.log('ExportComponent init');
  console.log(this.consultService.response);
  this.application = this.consultService.response;

  this.appID= this.consultService.response.dataList.find(pair => 'PROCEDURE' === pair.field)
      ? this.consultService.response.dataList.find(pair => 'PROCEDURE' === pair.field).value : null;
}

```

Thank you.