|data||A data object containing JSON data|
|opt||Options for reading the JSON data and creating the Foundation objects.|
|error||If an error occurs, upon return contains an NSError object that describes the problem.|
NSJSONSerialization is Available in iOS 5.0 and later An object that may be converted to JSON must have the following properties:
The top level object is an NSArray or NSDictionary.
All objects are instances of NSString, NSNumber, NSArray, NSDictionary, or NSNull.
All dictionary keys are instances of NSString.
Numbers are not NaN or infinity.