Trying to convert specific Json with JSON.NET gives me Error Converting Value

Question

I am actually implementing some new functionality for my company's app, the previous dev already did some similar deserialization with JSON.NET successfully and I was trying to make it work with my new functionality.

Here is the object I am trying to deserialize:

"{
 \"@type\":[\"IN.history.1\"],
 \"@self\":\"/history\",
 \"history\":[
  \"195166208;
  2021-09-06T11:48:26.164;
  User Modified;
  TA_NONE;
  1.1.System.4.1;
  \\u0003D\\u0001 = \\u0001\\n\\u0006 = Standard\\nIsMandatory = No\\nModifiedUser_ID = 3\\nModifiedUser_Name = BIS Benutzer\\nModifierUser_ID = 3\\nModifierUser_Name = BIS Benutzer\\nSource_Name = RPS\\nSource_ReportingNumber = 0\\n\"
 ]
}"

To be able to store it I created two classes:

        public class HistoryList
        {
            public string eventID { get; set; }
            public string timestamp { get; set; }
            public string eventName { get; set; }
            public string ta { get; set; }
            public string siid { get; set; }
            public string parameters { get; set; }
        }

        public class GetHistory
        {
            public List<string> type { get; set; }
            public string self { get; set; }
            public List<HistoryList> history { get; set; }
        }

Here is my call to the deserialization method:

        internal List<HistoryList> GetHistory(int maxEvents)
        {
            string response = GetJson(_url + "/history?maxevents=" + Convert.ToString(maxEvents));
            response = response.Replace("@", "");
            return JsonConvert.DeserializeObject<MAP5000Classes.GetHistory>(response).history;
        }

I already noticed I had to get rid of the @, but I still get a conversion error with my class HistoryList(Could not cast or convert from System.String to HistoryList.), I probably made some mistake with my class...

Help would be much appreciated !

Answer 1

You cannot deserialize HistoryList like that. It's just an array containing a single string, there is no inherent meaning in them being particular properties. Instead you will have to parse it out manually:

public class GetHistory
{
    public List<string> type { get; set; }
    public string self { get; set; }
    public List<string> history { get; set; }
}

var history = JsonConvert.DeserializeObject<MAP5000Classes.GetHistory>(response);
var strings = history.history[0].Split(new[]{';', '\r', '\n'}, StringSplitOptions.RemoveEmptyEntries);
return new HistoryList {
    eventID = strings[0],
    timestamp = strings[1],
    eventName = strings[2],
    ta = strings[3],
    siid = strings[4],
    parameters = strings[5],
};