Deserialize Json object with multiple possible child types

Question

I'm trying to deserialize an object that basically has an array of objects where each one has a property with object type and object instance. The schema looks somewhat like this:

public class MainObject
{
    public IEnumerable<Parent> Parents { get; set; }
}

public class Parent
{
    public string NameOfChildObjectType { get; set; }
    public Object Child { get; set; }
}

public class Child_1
{
    //some props
}

public class Child_2
{
    //some props but different as child 1 or 3
}

public class Child_3
{
    // completely different props literally the only thing we have in common is us being children
}

And Json file

{
    "id": "1",
    "Name": "MainObjectName",
    "Parents": [
        {
            "ChildName": "ChildOfType1",
            "Parameters": {
                "Name": "Jordan"
            }
        },
        {
            "ChildName": "ChildOfType2",
            "Parameters": {
                "Height": "6`2"
            }
        },
        {
            "ChildName": "ChildOfType3",
            "Parameters": {
                "OwnedPets": [
                    {
                        "DogName": "JJ",
                        "FishName": "Shrimp"
                    }
                ],
                "MaxHeadRotation": "45"
            }
        }
    ]
}

So is there any way I could define a generic type that isn't shared between all the objects in the list or even deserialize them in one go? Any ideas are appreciated.

Is this not working ? Setting Child's type to object should be all you need. — Laurent, Sep 16 '21 at 13:09
Does this answer your question? [Deserializing polymorphic json classes without type information using json.net](https://stackoverflow.com/questions/19307752/deserializing-polymorphic-json-classes-without-type-information-using-json-net) — Métoule, Sep 16 '21 at 13:34
@Métoule it kind of does, but I hoped in a more elegant solution — Michal Cikatricis, Sep 16 '21 at 13:48
@Laurent You cannot access properties without changing their types from object when the child type is Object or can you? — Michal Cikatricis, Sep 16 '21 at 13:49
@Michal Cikatricis Indeed, you'll have to cast the object to the type you want. Or use JsonDocument. — Laurent, Sep 16 '21 at 14:38

Serge · Accepted Answer · 2021-09-16T13:55:07.950

I tested this in Visual Studio, everything is working properly

var json= ... your json string

var jD = JsonConvert.DeserializeObject<Root>(json);

classes

public class Root
{
    public string id { get; set; }
    public string Name { get; set; }
    public List<Parent> Parents { get; set; }
}

public class OwnedPet
{
    public string DogName { get; set; }
    public string FishName { get; set; }
}

public class Parameters
{
    public string Name { get; set; }
    public string Height { get; set; }
    public List<OwnedPet> OwnedPets { get; set; }
    public string MaxHeadRotation { get; set; }
}

public class Parent
{
    public string ChildName { get; set; }
    public Parameters Parameters { get; set; }
}

you can try to use Dictionary<string, object> instead of Parameters class, but in any case after this you will need classes to convert from object to type. I can't imagine how are you going to use data if you don't know what is inside of object

Well this does solve my problem and I wanted to check for typeof(parameters) when I filter it so I know what I can do with it however the type is already in parent object and when I use all those children object types as interfaces for some "big child" guess ill at least be able to use the properties I just need to be careful not to use the wrong ones with the particular child type... — Michal Cikatricis, Sep 16 '21 at 14:07

Deserialize Json object with multiple possible child types

1 Answers1