title: Extract data from respone Angular 2
body: <p>I have 1 component and 1 service. </p>
  
  <p>Component element : </p>
  
  <pre><code>...
  constructor(private requestService : RequestService)
  {
  
  }
  ngOnInit()
  {
      this.a = this.requestService.send_request(urlWebAPI);
      console.log(this.a);
  }
  ...
  </code></pre>
  
  <p>Service:</p>
  
  <pre><code>constructor(private http: Http) 
  {
      this.http = http; 
      this.headers = new Headers
      ({
          'Content-Type': 'application/json'
      });
  }
  
  send_request(additional_url: String) 
  {       
      return this.http.post(this.url + additional_url, {headers: this.headers})
          .toPromise()
          .then(response =&gt; response.json())
          .catch(this.handleError);
  }
  private handleError(error: any) 
  {
      console.error('An error occurred', error);
      return Promise.reject(error.message || error);
  }
  </code></pre>
  
  <p>But this is what I get printed...How I can directly extract 'listaUniversita' array from this request?
  <a href="https://i.stack.imgur.com/L51YM.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/L51YM.png" alt="enter image description here"></a></p>