title: Check that folder contains files with specific extension (windows bat file)
body: <p>Hi I am trying to create a windows bat file that checks if a folder contains files of a specify extension and the runs some basic command. Something like:</p>
  
  <pre><code>set inputFolder=%1
  
  if [%inputFolder%.containsExtension("class")] goto exists
  
  goto end
  :exists
  
  :end
  </code></pre>
  
  <p>but how do I check the extension of the files in inputFolder?</p>