How to handle Json resull with null

hi, new to Json. I m a newbie on Json REST.

1) here the Json result :

{
  "Status": 0,
  "AlertCode": 0,
  "Message": null,
  "Results": {
    "Case_ID": 543061,
    "Case_Ref_Num": "100549642",
    "Case_Caller_Info": "Customer ABC",
    "Case_Caller_Tel": null,
    "Case_Caller_Company": " Customer ABC"
  }
}

2) using Json2csharp to generate the classes for the above json result:

public class Results
{
    public int Case_ID { get; set; }
    public string Case_Ref_Num { get; set; }
    public string Case_Caller_Info { get; set; }
    public object Case_Caller_Tel { get; set; }
    public string Case_Caller_Company { get; set; }
}

public class RootObject
{
    public int Status { get; set; }
    public int AlertCode { get; set; }
    public object Message { get; set; }
    public Results Results { get; set; }
}

I would like to know how to handle the null like   "Message": null

How to loop thru the Json Result?

Thanks