title: OpenFileDialog - only display filenames that have no extensions
body: <p>I have the following code in my C# program:</p>
  
  <pre><code>        OpenFileDialog fDialog = new OpenFileDialog();
          fDialog.Title = "Open a file";
          fDialog.Filter =
             "NCF files (*.ncf)|*.ncf|All files (*.*)|*.*|No Extensions (*.)|*.";
  </code></pre>
  
  <p><br/><br/>
  I want to be able to have the user pick from the following:
  <br/><br/>
  <b>*.NCF</b> (files with .NCF extension only)<br/>
  <b>**.*</b> (all files)</p>
  
  <p>and files that have <b>no extensions</b> such as:<br/><br/>
  <b>filewithnoextension</b>
  <br/><br/><br/><br/>
  I know ***.*  will do this, but it also displays the .NCF, .TXT, and all other files in the same directory.  <br/><br/>I just want to be able to display filenames that have no extensions.
  <br/><br/><br/><br/>
  Filtering with *. does not do the trick.  It works fine when doing it with a DOS window (<b>dir *.</b>) , but C# seems to ignore the *. filter.</p>
  
  <p><br/><br/><br/><br/>
  Is there a way I can do this with C#?</p>
  
  <p>Thanks.</p>