title: FileReader: get file name
body: <p>I have a FileReader with an Observable which looks like this:</p>
  
  <pre><code>readDocument(fileChangeEvent: Event) {
      return new Observable&lt;Object&gt;(obs =&gt; {
          const file = (fileChangeEvent.target as HTMLInputElement).files[0];
          if (file) {
              const fileReader = new FileReader();
              fileReader.onload = (e) =&gt; {
                  obs.next(fileReader.result);
              }
              fileReader.readAsText(file);
          }
      });
  }
  </code></pre>
  
  <p>I use the content of the file in the subscription:</p>
  
  <pre><code>this.readDocument(document).subscribe(content =&gt; {
  
  }
  </code></pre>
  
  <p>In the subscription, how could i get the name of the file? </p>
  
  <p>something like this:</p>
  
  <pre><code>   this.readDocument(document).subscribe(content =&gt; {
          filename = content.getfilename;
      }
  </code></pre>
  
  <p>Is this possible? what could be a solution here?</p>