http://groups.google.com/group/jayrock/t/878df871a14df35b

JayrockInterfaceExportDemo.cs

// Demo for:
// http://groups.google.com/group/jayrock/t/878df871a14df35b

using System;
using Jayrock.Json;
using Jayrock.Json.Conversion;

interface IFoo
{
    string Text { get; }
}

class Bar : IFoo
{
    public string Text { get { return "Bar"; } }
}

class Baz : IFoo
{
    public string Text { get { return "Baz"; } }
}

internal class FooExporter<T> : IExporter where T : IFoo
{
    public Type InputType { get { return typeof(T); } }

    void IExporter.Export(ExportContext context, object value, JsonWriter writer)
    {
        Export(context, (T) value, writer);
    }

    public virtual void Export(ExportContext context, T value, JsonWriter writer)
    {
        writer.WriteStartObject();
        writer.WriteMember("text");
        context.Export(value.Text.ToUpperInvariant(), writer);
        writer.WriteEndObject();
    }
}

public class Program
{
	public static void Main()
	{
	    var ec = new ExportContext();
        
        ec.Register(new FooExporter<Bar>());
        ec.Register(new FooExporter<Baz>());
        
        ec.Export(new Bar(), new JsonTextWriter(Console.Out));
        ec.Export(new Baz(), new JsonTextWriter(Console.Out));
    }
}