title: Get JSON sub element from NSDictionary
body: <p>I have the following JSON format stored in an NSDictionary. How would I extract <code>audio_link</code>?</p>
  
  <pre><code>{
    "results": [
      {
        "audio_link": "http://www.website.com/Alive.mp3",
        "author": "John",
        "date_created": "2014-02-17 05:12:25"
      }
    ]
  }
  </code></pre>
  
  <p>I have tried </p>
  
  <pre><code>NSString * songUrl = [[json objectForKey:@"results"] objectForKey:@"url"];
  </code></pre>
  
  <p>but that failed.</p>