title: iPhone SDK - How to check files' name in document folder?
body: <p>Users can upload images (jpg or png) from computer to iPhone, and images will be stored in app document folder.</p>
  
  <p>My questions are </p>
  
  <ol>
  <li><p>how to check the names of images that are currently in document folder? </p></li>
  <li><p>how to identify it is a jpg or png?</p></li>
  </ol>
  
  <p>Thanks in advance!:)</p>