title: Remove file extension from a file name string
body: <p>If I have a string saying <code>"abc.txt"</code>, is there a quick way to get a substring that is just <code>"abc"</code>?</p>
  
  <p>I can't do an <code>fileName.IndexOf('.')</code> because the file name could be <code>"abc.123.txt"</code> or something and I obviously just want to get rid of the extension (i.e. <code>"abc.123"</code>).</p>