title: Delete all my NSUserDefaults that start with a certain word
body: <p>Is there a way for me to "walk" through a list of all the <code>NSUserDefault</code>s in my iPhone app, and only delete certain ones?</p>
  
  <p>For example, I'd like to get all the key names that start with a certain word.</p>
  
  <p>Something like this:</p>
  
  <pre><code>[[NSUserDefaults standardUserDefaults] removeObjectForKey:@"Dog*"];
  </code></pre>