title: How can I catch NULL exceptions in iOS from json
body: <p>My app is pretty much complete and we are in the testing phase. I noticed that in our database, there are numerous json data that return null, but not a majority. Sometimes the first name data will be null and the last name will have data, or vice versa. My app crashes when it receives an instance that is NULL. </p>
  
  <p>How can I catch this NULL and make an exception for it (for ALL different fields of the json data)? </p>