ReadModel.cs

public class InventoryListView : Handles<InventoryItemCreated>, Handles<InventoryItemRenamed>, Handles<InventoryItemDeactivated>
{
    public void Handle(InventoryItemCreated message)
    {
        FakeDatabase.list.Add(new InventoryItemListDto(message.Id, message.Name));
    }

    public void Handle(InventoryItemRenamed message)
    {
        var item = FakeDatabase.list.Single(x => x.Id == message.Id);
        item.Name = message.NewName;
    }

    public void Handle(InventoryItemDeactivated message)
    {
        FakeDatabase.list.RemoveAll(x => x.Id == message.Id);
    }
}

public class InventoryItemDetailView :
    Handles<InventoryItemCreated>,
    Handles<InventoryItemDeactivated>,
    Handles<InventoryItemRenamed>,
    Handles<ItemsRemovedFromInventory>,
    Handles<ItemsCheckedInToInventory>
{
    public void Handle(InventoryItemCreated message)
    {
        FakeDatabase.details.Add(message.Id, new InventoryItemDetailsDto(message.Id, message.Name, 0, 0));
    }

    public void Handle(InventoryItemRenamed message)
    {
        InventoryItemDetailsDto d = GetDetailsItem(message.Id);
        d.Name = message.NewName;
        d.Version = message.Version;
    }

    private InventoryItemDetailsDto GetDetailsItem(Guid id)
    {
        InventoryItemDetailsDto d;

        if (!FakeDatabase.details.TryGetValue(id, out d))
        {
            throw new InvalidOperationException("did not find the original inventory this shouldnt happen");
        }

        return d;
    }

    public void Handle(ItemsRemovedFromInventory message)
    {
        InventoryItemDetailsDto d = GetDetailsItem(message.Id);
        d.CurrentCount -= message.Count;
        d.Version = message.Version;
    }

    public void Handle(ItemsCheckedInToInventory message)
    {
        InventoryItemDetailsDto d = GetDetailsItem(message.Id);
        d.CurrentCount += message.Count;
        d.Version = message.Version;
    }

    public void Handle(InventoryItemDeactivated message)
    {
        FakeDatabase.details.Remove(message.Id);
    }
}