Deserialize nested JSON into C# objects

Question

I am getting JSON back from an API that looks like this:

{
  "Items": {
    "Item322A": [{
      "prop1": "string",
      "prop2": "string",
      "prop3": 1,
      "prop4": false
    },{
      "prop1": "string",
      "prop2": "string",
      "prop3": 0,
      "prop4": false
    }],
       "Item2B": [{
      "prop1": "string",
      "prop2": "string",
      "prop3": 14,
      "prop4": true
    }]
  },
  "Errors": ["String"]
}

I have tried a few approaches to represent this JSON in c# objects (too many to list here). I've tried with lists and dictionaries, here is a recent example of how I've tried to represent it:

    private class Response
    {
        public Item Items { get; set; }
        public string[] Errors { get; set; }
    }

    private class Item
    {
        public List<SubItem> SubItems { get; set; }
    }

    private class SubItem
    {
        public List<Info> Infos { get; set; }
    }

    private class Info
    {
        public string Prop1 { get; set; }
        public string Prop2 { get; set; }
        public int Prop3 { get; set; }
        public bool Prop4 { get; set; }
    }

And here is the method I am using to deserialize the JSON:

    using (var sr = new StringReader(responseJSON))
    using (var jr = new JsonTextReader(sr))
    {
        var serial = new JsonSerializer();
        serial.Formatting = Formatting.Indented;
        var obj = serial.Deserialize<Response>(jr);
    }

obj contains Items and Errors . And Items contains SubItems , but SubItems is null . So nothing except for Errors is actually getting deserialized.

It should be simple, but for some reason I can't figure out the correct object representation

Answer 1

Use this this site for representation:

https://quicktype.io/csharp/

something like this may help you

public class Item322A
{
    public string prop1 { get; set; }
    public string prop2 { get; set; }
    public int prop3 { get; set; }
    public bool prop4 { get; set; }
}

public class Item2B
{
    public string prop1 { get; set; }
    public string prop2 { get; set; }
    public int prop3 { get; set; }
    public bool prop4 { get; set; }
}

public class Items
{
    public List<Item322A> Item322A { get; set; }
    public List<Item2B> Item2B { get; set; }
}

public class jsonObject
{
    public Items Items { get; set; }
    public List<string> Errors { get; set; }
}

Here is how to deserialize (use JsonConvert class):

jsonObject ourlisting = JsonConvert.DeserializeObject<jsonObject>(strJSON);

Answer 2

For "Items" use a Dictionary<string, List<Info>> , ie:

class Response
{
    public Dictionary<string, List<Info>> Items { get; set; }
    public string[] Errors { get; set; }
}

class Info
{
    public string Prop1 { get; set; }
    public string Prop2 { get; set; }
    public int Prop3 { get; set; }
    public bool Prop4 { get; set; }
}

This assumes that the item names "Item322A" and "Item2B" will vary from response to response, and reads these names in as the dictionary keys.

Sample fiddle .

Answer 3

You could use Json.Parse so that you can query into the data -- and just use the single model.

private class Info
{
    public string Prop1 { get; set; }
    public string Prop2 { get; set; }
    public int Prop3 { get; set; }
    public bool Prop4 { get; set; }
}

var result = JObject.Parse(resultContent);   //parses entire stream into JObject, from which you can use to query the bits you need.
var items = result["Items"].Children().ToList();   //Get the sections you need and save as enumerable (will be in the form of JTokens)

List<Info> infoList = new List<Info>();  //init new list to store the objects.

//iterate through the list and match to an object. If Property names don't match -- you could also map the properties individually. Also useful if you need to dig out nested properties.
foreach(var subItem in items){
foreach(JToken result in subItem){
Info info = result.ToObject<Info>();
infoList.add(info);
}}