How to call json after deserializing?

Question

I bring my Json data in using the downloadstring() function. I then deserialize it (will show below) but I am not sure what happens to the data after that. I don't know how to call it or how to manipulate it, let alone find it. I'm new to Json, this is obviously a really easy question, but I can't figure it out.

Here is the code

var data = c.DownloadString("http:...");
dynamic jsdonData = JsonConvert.DeserializeObject<dynamic>(data);
Console.WriteLine(jsonData);?????????????????

The Json Data looks similar to this.

"$id":"1",
  "$values":[  
    {  
      "$id":"2",
      "ID":....,
      "MSSCompanyID":....,
      "CircuitID":"....",
      "CompanyName":"...",
      "Metrics":{  
        "$id":"3",
        "$values":[  
          {  
            "$id":"4",
            "longId":1164568,
            "unit":"......",
            "name":"...."
          },
          {  
            "$id":"5",
            "longId":1164757,
            "unit":".....",
            "name":"......"
          }
        ]
      }
    },
    {  
      "$id":"6",
      "ID":....,
      "MSSCompanyID":......,
      "CircuitID":"......",
      "CompanyName":"....",
      "Metrics":{  
        "$id":"7",
        "$values":[  
          {  
            "$id":"8",
            "longId":...,
            "unit":".......",
            "name":"......."
          },
          {  
            "$id":"9",
            "longId":1164757,
            "unit":"......",
            "name":".........."
          }
        ]
      }
    },    

The Json is valid, the downloadstring DOES pull the json like it should. I am not sure about the deserializing though.

Answer 1

Another answer is to use NuGet to grab JSON.NET.

Create a POCO class that could represent a JSON object:

public class CompanyDetails
{
    public int ID { get; set; }

    public int MSSCompanyID { get; set; }

    public int CircuitID { get; set; }

    public string CompanyName { get; set; }

    public Metric[] Metrics { get; set; }
}

public class Metric
{
    public int LongId { get; set; }

    public string Unit { get; set; }

    public string Name { get; set; }
}

HINT: If you don't care about a certain object not being deserialised, you can make the type of that property ExpandoObject, which means C# will take care of "creating" the necessary dynamic class structures. ExpandoObject is basically dynamic.

Using JsonConvert from the JSON.NET library you can deserialise it like this:

public CompanyDetails[] GetDetails(string json)
{
    // this adds automatic camel casing conversions
    JsonConvert.DefaultSettings = () => new JsonSerializerSettings { ContractResolver = new CamelCasePropertyNamesContractResolver() };

    return JsonConvert.DeserializeObject<CompanyDetails[]>(json);
}

So now, you will have your JSON deserialised into a lovely C# object graph. You can now traverse this till your hearts content. Even chuck in the composite or visitor pattern if you want.

REMEMBER: I use CompanyDetails[] this could also be ICollection<>, Collection<>, IEnumerable<> or List<> etc. etc.

Answer 2

Personally the following is how I have deserialized a Json string similar to yours above:

public static T DeSerializeJSon<T>(string JSON)
    {
        using (MemoryStream stream = new MemoryStream())
        {
            DataContractJsonSerializer ds = new DataContractJsonSerializer(typeof(T));
            var bytes = Encoding.UTF8.GetBytes(JSON);
            stream.Write(bytes, 0, bytes.Length);                
            stream.Position = 0;
            T jsonobject = (T)ds.ReadObject(stream);
            return jsonobject;
        }
    }

As you can see it is easier to manipulate this string once deserialized because it will be contained within an object.

For your reference here is how I would then serialize:

       public static string SerializeJSon<T>(T objectData)
    {
        using (MemoryStream stream = new MemoryStream())
        {
            DataContractJsonSerializer ds = new DataContractJsonSerializer(typeof(T));
            ds.WriteObject(stream, objectData);
            return Encoding.UTF8.GetString(stream.ToArray());
        }
    }

These are both static methods as they are contained within a class library I have created to save code duplication.

Hopefully this sheds a little more light :)