Serializing base class with discriminator property results in KeyNotFoundException about jsonsubtypes HOT 1 CLOSED

Hi @CK-Yong

Thanks for submitting this issue

I don't agree with the expectation that unregistered base class should serialize their class name because the "discriminator's value" may be numeric or have a specific naming convention (with specific prefix/suffix or another)

When using JsonSubtypesConverterBuilder all sub types should be registered:

          var serializersettings = new JsonSerializerSettings();
            serializersettings.Converters.Add(
                JsonSubtypesConverterBuilder
                    .Of(typeof(Animal2), "Type")
                    .SerializeDiscriminatorProperty()
                    .RegisterSubtype(typeof(Animal), typeof(Animal).Name)
                    .RegisterSubtype(typeof(Cat), typeof(Cat).Name)
                    .Build());

However, I agree that the exception KeyNotFoundException is not explicit enough and should be fixed

from jsonsubtypes.