title: How to get file ID in google apps scripts
body: <p>I am trying to get the ID of the doc that I am working on. Currently I am using</p>
  
  <pre><code>var files = DriveApp.getFileById('whatever the doc Id is')
  </code></pre>
  
  <p>and this works fine. However, I want to be able to get any document Id that this application may be running on. I don't want the user to go into the code and switch the ID depending on what document they are on. If anyone has any ideas I would love to hear them,</p>
  
  <p>Thanks</p>