title: How to check if System.Net.WebClient.DownloadData is downloading a binary file?
body: <p>I am trying to use <code>WebClient</code> to download a file from web using a WinForms application. However, I really only want to download HTML file. Any other type I will want to ignore.</p>
  
  <p>I checked the <code>WebResponse.ContentType</code>, but its value is always <code>null</code>. </p>
  
  <p>Anyone have any idea what could be the cause?</p>