Background:

I'm invoking a web service method which returns a JSON string. This string can be of type ASConInfo or ASErrorResponse.

Question:

Using the DataContractJsonSerializer, how can I convert the returned JSON string to one of those objects?

Thanks in advance

I have tried the following technique, but it does not work:

    public static object test(string inputString)
    {
        object obj = null;
        using (MemoryStream ms = new MemoryStream(Encoding.Unicode.GetBytes(inputString)))
        {
            DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(object));
            obj = ser.ReadObject(ms) as object;
        }
        return obj;
    }

  [WebMethod]
    public string TypeChecker()
    {
        string str = "{\"Error\":191,\"ID\":\"112345678921212\",\"Length\":15}";
        //string strErro = "";

        object a = test(str);

        if (a is ASResponse)
        {
            return "ASResponse"; 
        }

        if (a is ASErrorResponse)
        {
            return "ASErrorResponse";
        }

        return "Nothing";
    }