Using a custom type discriminator to tell JSON.net which type of a class hierarchy to deserialize

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In case you are still looking, here is an example: http://james.newtonking.com/archive/2011/11/19/json-net-4-0-release-4-bug-fixes.aspx

This will allow you to create a table based mapping:

public class TypeNameSerializationBinder : SerializationBinder
{
    public TypeNameSerializationBinder(Dictionary<Type, string> typeNames = null)
    {
        if (typeNames != null)
        {
            foreach (var typeName in typeNames)
            {
                Map(typeName.Key, typeName.Value);
            }
        }
    }

    readonly Dictionary<Type, string> typeToName = new Dictionary<Type, string>();
    readonly Dictionary<string, Type> nameToType = new Dictionary<string, Type>(StringComparer.OrdinalIgnoreCase);

    public void Map(Type type, string name)
    {
        this.typeToName.Add(type, name);
        this.nameToType.Add(name, type);
    }

    public override void BindToName(Type serializedType, out string assemblyName, out string typeName)
    {
        var name = typeToName.Get(serializedType);
        if (name != null)
        {
            assemblyName = null;
            typeName = name;
        }
        else
        {
            assemblyName = serializedType.Assembly.FullName;
            typeName = serializedType.FullName;                
        }
    }

    public override Type BindToType(string assemblyName, string typeName)
    {
        if (assemblyName == null)
        {
            var type = this.nameToType.Get(typeName);
            if (type != null)
            {
                return type;
            }
        }
        return Type.GetType(string.Format("{0}, {1}", typeName, assemblyName), true);
    }
}

The code has a slight defect in that if a type name mapping is attempted where the type is unique but the name is already used, the Map method will throw an exception after the type-to-name mapping is already added leaving the table in an inconsistent state.

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