Question - Serializing & Deserializing objects with inheritance

[tomkerkhove]

I'm trying to understand the serialization & deserialization of objects a bit and how this works with inheritance.

If I have a class Factory:

public class Factory
{
    public List<ICar> Cars { get; } = new List<ICar>();
}

Where ICar specifies the following:

public interface ICar
{
    string LicensePlate { get; set; }
    Make Make { get; set; }
}

Then I have different objects per car make such as Ford

public class Ford : Car, ICar
{
    public Make Make { get; set; } = Make.Ford;
    public bool HasSpareTier { get; set; }
}

Which uses Car:

public class Car
{
    public string LicensePlate { get; set; }
}

This perfectly serializes as following:

cars:
- make: Ford
  hasSpareTier: true
  licensePlate: 4391bbc9-af5c-4f50-adf4-85a522508267
- isDiesel: true
  licensePlate: 311c11ea-ca03-4525-9f9a-56fa6764b100
- hasAutomaticBreak: true
  make: Volvo
  licensePlate: 53a5c3c9-04f3-4573-9e4b-48a63befbd19

Stupid questions inbound:

• How do I deserialize my objects so that I can cast them to Ford instead of ICar?
• Should I use the YamlStream instead and parse it myself? This brings a lot of overhead that I would like to avoid (sample)

NuGet Version

YamlDotNet v5.0.1

Full Repro

You can find a repro of what I want to achieve here

This currently throws an exception but I'm honestly not sure why:

SerializationException: Property 'cars' not found on type TomKerkhove.YamlGenerics.Tests.Model.Factory'.

[tomkerkhove]

I went for the YamlStream approach but would be good to know if this is coming/possible with the simple approach.

[Arakade]

I believe the answer is "Tagging" -- see https://github.com/aaubry/YamlDotNet/wiki/Serialization.Deserializer#withtagmappingstring-type
You register the mapping from a Ford to a tagged name with both serializer and deserializer and the former will output tags in the YAML stream to indicate the subtype and the latter will deserialize to the specific sub-type.
Have just implemented in our project to serialize and deserialize polymorphic classes implementing a single interface (declared as [YamlMember].
HTH

[BBoldenow-Alt]

@Arakade is correct - I do inheritance in this way.

[EdwardCooke]

Since this issue now has a really good answer I'm going to close it. Thanks @Arakade .