How to get the value from a Complex JSON Object

Question

I am getting the JSON request from http://www.viki.com/api/v2/channels.json

Now, I have the following classes from JSON:

public class RootObject
{
    public int id { get; set; }
    public string title { get; set; }
    public string description { get; set; }
    public string uri { get; set; }
    public List<Episode> episodes { get; set; }
    public Thumbnails2 thumbnails { get; set; }
    public string timestamp { get; set; }
    public List<object> genres { get; set; }
    public string origin_code { get; set; }
}

public class Thumbnails2
{
    public string c_220_160 { get; set; }
    public string c_102_102 { get; set; }
    public string c_180_130 { get; set; }
    public string c_110_80 { get; set; }
    public string xl { get; set; }
    public string large { get; set; }
    public string medium { get; set; }
    public string small { get; set; }
    public string c_320_300 { get; set; }
    public string c_640_600 { get; set; }
    public string c_95_70 { get; set; }
    public string c_190_140 { get; set; }
    public string c_280_200 { get; set; }
    public string c_560_400 { get; set; }
}

Now I want to get the Values from large and medium in Thumbnails2 and all the episodes in List.

I tried with:

using (var wc = new WebClient())
{
  var json = wc.DownloadString(jsonRequestURL);

  dynamic vikiDesrialized = JsonConvert.DeserializeObject(json);
  foreach (var item in vikiDesrialized)
  {
     //Console.WriteLine(item.title);

     foreach (var thumnails in item.thumbnails)
     {
          JsonConvert.DeserializeObject(thumbNails);
     }
  }
}

But getting an exception which implies something else:

'The invocation of the constructor on type 'Viki.MainWindow' that matches the specified binding constraints threw an exception.' Line number '3' and line position '9'.

Can I have those values using LINQ?

Answer 1

You don't need the second deserialization JsonConvert.DeserializeObject(thumbNails);

either use

foreach (var item in dynObj)
{
    Console.WriteLine(item.title);
    Console.WriteLine(item.thumbnails.small);
}

or

using (var wc = new WebClient())
{
    var json = wc.DownloadString("http://www.viki.com/api/v2/channels.json");
    var rootObj = JsonConvert.DeserializeObject<RootObject[]>(json);

    var obj = rootObj.Select(r=>new 
                {
                    Title = r.title,
                    Thumbnail = r.thumbnails.small
                }).ToArray();
}

Answer 2

Wouldn't it be an easier way to use DataContracts and use the DataContractJsonSerializer

I have used it so far only with deserialization from JSON Objects from a File, but its so easy.

Just declare the Class with the atribute [DataContract] and each member that should deserialized with [DataMember]

eg (from my code)

[DataContract]
public class CharacteristicManager
{
  [DataMember(Order = 1)]
  public Characteristic[] characteristics;
  private Dictionary<String, Characteristic> characteristic_dictionary;
 }

Deserialization looks like this:

DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(CharacteristicManager));

CharacteristicManager cm = (CharacteristicManager)ser.ReadObject(stream);

DataContractJsonSerializer will build the whole Object recursively including Arrays, Lists, Dictionarys.

Best Thomas