title: Windows batch file match prefix and suffix in filenames
body: <p>Within an Windows batch file, is it possible to extract <code>somestring</code> when files are named this way:  </p>
  
  <pre><code>prefix_somestring.txt
  somestring_suffix.txt 
  </code></pre>
  
  <p>Assuming the underscore <code>_</code> separating the prefix or suffix. The context is to iterate through all files in a folder and return <code>somestring</code> for each file. </p>