deserialize json into .net object using json.net

Question

I am having a problem deserializing some JSON string back into .net objects. I have a container class which contains some information from external and there is a field call ClassType which defined what type of information is that and the actual content is in another property, which currently can be anything, so we define that as an Object type.

Following are the .net class definition which helps to understand the issue.

class ClassOne
{
    public string Name { get; set; }
    public int Age { get; set; }
}

class ClassTwo
{
    public string AddressLine { get; set; }
    public string AddressLine2 { get; set; }
}

class ClassThree
{
    public string Country { get; set; }
    public string Passport { get; set; }
}

class ContainerClass
{
    public string ClassType { get; set; }
    public object ClassContent { get; set; }
}

When getting the information from external in a JSON format it will be something like:

{"ClassType":"Class1","ClassContent":{"Name":"James","Age":2}}

I am using Newtonsoft JSON.net library to deserialize the JSON string. It seems like that the default deserialize function will just deserialize that into an Newtonsoft.Json.Linq.JContainer. I just wondering how can I write some Converter to deserialize the ClassContent based on the ClassType definition. Any code sample will be highly appreciated.

Answer 1

I would go dynamic way, like:

string json = @"{""ClassType"":""Class1"",""ClassContent"":{""Name"":""James"",""Age"":2}}";

dynamic jObj = JObject.Parse(json);
if (jObj.ClassType == "Class1")
{
    Console.WriteLine("{0} {1}", jObj.ClassContent.Name, jObj.ClassContent.Age);
}

Since returning an object (ClassContent) doesn't mean much, and you have to cast it to a concrete class somehow (using some if's or switch).

Answer 2

Sample:

var container = JsonConvert.DeserializeObject<ContainerClass>(json);
JContainer content = (JContainer)container.ClassContent;

switch(container.ClassType)
{
    case "Class1": return container.ToObject(typeof(ClassOne));
    ..    
}

Answer 3

use dynamic and call .ToObject(Type type)

dynamic root = JObject.Parse(json)
return root["ClassContent"].ToObject(Type.GetType(root["ClassType"]))

Answer 4

Try the following

 var jsonObject = JObject.Parse(jsonString);

 var result = jsonObject.ToObject(Type.GetType("namespace.className"));