Objective C Checking JSON format

In iOS applications, We use JSON format for web services as it is fast and easy to parse. JSON could be either in array or in dictionary format. It is a good practice to JSON format before parsing the response from a web service though we have perfect handshake with web service developers.

Let's take an example of fetching all the employees using a web service and there is a chance of JSON coming in any format as shown below.

JSON Dictionary:

 {"employees":

   [

     {"firstName":"Tim", "lastName":"Cook"},

     {"firstName":"Will", "lastName":"Smith"},

     {"firstName":"Leonardo", "lastName":"Dicaprio"}

   ]

 }

JSON Array:

 [

    {"firstName":"Tim", "lastName":"Cook"},

    {"firstName":"Anna", "lastName":"Smith"},

    {"firstName":"Peter", "lastName":"Jones"}

 ]

Using introspection methods in Objective C, We can check the type of JSON.

                         

  if([response isKindOfClass:[NSArray class]]){

      //JSON is in Array Format

  }

  if([response isKindOfClass:[NSDictionary class]]){

      //JSON is in Dictionary Format

  }

Hope this post is useful. Feel free to comment in case of any queries.