JSON.NET Resolving Nested Data Types

Question

I'm new to JSON.NET, and I've been playing with the new Marvel API that was recently released.

When I call this API it will return the following JSON Data Structure:-

{  
    "code": 200,   
    "status": "Ok",   
    "etag": "f0fbae65eb2f8f28bdeea0a29be8749a4e67acb3",   
    "data": 
    {     
        "offset": 0,    
        "limit": 20,     
        "total": 30920,     
        "count": 20,     
        "results": [{array of objects}}]  
    } 
}

I can create Classes for this Data like this :

public class Rootobject
{
    public int code { get; set; }
    public string status { get; set; }
    public string etag { get; set; }
    public Data data { get; set; }
}

public class Data
{
    public int offset { get; set; }
    public int limit { get; set; }
    public int total { get; set; }
    public int count { get; set; }
    public Result[] results { get; set; }
}

public class Result
{

}

Now, my issue. The Results that come back from the API can relate to different Objects, it could be results relating to Characters, Comics, Series etc. The objects all hold different properties.

I need to be able to swap out the Result Class properties based on the Entity Type that the results relate too?

Can this actually be done?

Answer 1

As promised, I've posted the anser to this problem. It turns out that the JSON response has nested data covering all related data-types, very much like a relational database.

I found something really cool, I basically made a request to the API and converted its response to a string. I then used the debugger to take a copy of the contents to the clipboard.

I created a new Class and Called it MarvelResponse.

I added the NewtonSoft.Json directive to the file, and used the Paste Special option from Edit Menu in VS2012. Here you can paste the option "Paste as JSON CLasses".

After some minor tweaking here is what it provided :-

namespace Kaiser.Training.Data.JSONClasses
{

    public class MarvelResponse
    {
        public int code { get; set; }
        public string status { get; set; }
        public string etag { get; set; }
        public Data data { get; set; }
    }

    public class Data
    {
        public int offset { get; set; }
        public int limit { get; set; }
        public int total { get; set; }
        public int count { get; set; }
        public Result[] results { get; set; }
    }

    public class Result
    {
        public int id { get; set; }
        public string name { get; set; }
        public string description { get; set; }
        public DateTime modified { get; set; }
        public Thumbnail thumbnail { get; set; }
        public string resourceURI { get; set; }
        public Comics comics { get; set; }
        public Series series { get; set; }
        public Stories stories { get; set; }
        public Events events { get; set; }
        public Url[] urls { get; set; }
    }

    public class Thumbnail
    {
        public string path { get; set; }
        public string extension { get; set; }
    }

    public class Comics
    {
        public int available { get; set; }
        public string collectionURI { get; set; }
        public ComicResourceUriItem[] items { get; set; }
        public int returned { get; set; }
    }

    public class ComicResourceUriItem
    {
        public string resourceURI { get; set; }
        public string name { get; set; }
    }

    public class Series
    {
        public int available { get; set; }
        public string collectionURI { get; set; }
        public SeriesResourceItem[] items { get; set; }
        public int returned { get; set; }
    }

    public class SeriesResourceItem
    {
        public string resourceURI { get; set; }
        public string name { get; set; }
    }

    public class Stories
    {
        public int available { get; set; }
        public string collectionURI { get; set; }
        public StoriesResourceItem[] items { get; set; }
        public int returned { get; set; }
    }

    public class StoriesResourceItem
    {
        public string resourceURI { get; set; }
        public string name { get; set; }
        public string type { get; set; }
    }

    public class Events
    {
        public int available { get; set; }
        public string collectionURI { get; set; }
        public EventsResourceUriItem[] items { get; set; }
        public int returned { get; set; }
    }

    public class EventsResourceUriItem
    {
        public string resourceURI { get; set; }
        public string name { get; set; }
    }

    public class Url
    {
        public string type { get; set; }
        public string url { get; set; }
    }

}

This was a huge help! Hope someone else finds it useful.

Answer 2

You can use var jObj = JObject.Parse(jsonString) then discover what object type it is by which properties are available on the object.

jObj["someComicSpecificProperty"] != null

However this is not full proof and will need to be done on a per object basis for the results array.

An alternate approach I have seen people use is to have a property on the object that is "typeName".

However the root cause of this problem is that you are trying to strongly type a property that is not strongly typed. I would really recommend splitting these different types of results out into different properties so that you don't have this problem.