Help on C# custom marshaling

[jpogorman]

Hello,

I am trying to get c# custom marshaling working in a particular scenario but it does not appear to be working or not jumping into my marshaling class when I try to debug it. I am try to implement a performance improvement in the transfer of thousands of objects (ClientInfoDesc riptor) over a remote call. The objects all have a model object (IDataDrivenMod el) to describe them but there may only two or three model objects in total. These model object could be large objects. Instead of transfering duplicate models I would like to marshal in the model id and when I retrieve the objects on the client side I will un marshal the model id and lookup the model from the cache.

I would appreciate it if anyone could tell me where I may be going wrong or give me tips on how to better debug this custom marshaling. Or maybe there is a better way to get this performance improvement without custom marshaling?

Thanks,
JP

[Serializable]
public abstract class ADDInfoDescript or : IDDInfoDescript or
{
[MarshalAs(Unman agedType.Custom Marshaler, MarshalTypeRef = typeof(DDMarsha ler))]
private IDataDrivenMode l ddModel = null;
...
}

// Class that has attribute being customed marshaled
[Serializable]
public class ClientInfoDescr iptor : ADDInfoDescript or
{
...
}

// Marshaling class
public sealed class DDMarshaler : System.Runtime. InteropServices .ICustomMarshal er
{
private static DDMarshaler marshaler = null;
public static ICustomMarshale r GetInstance(str ing cookie)
{
if (marshaler == null)
{
marshaler = new DDMarshaler();
}
return marshaler;
}

public DDMarshaler()
{
}

public object MarshalNativeTo Managed(System. IntPtr pNativeData)
{
int id = Marshal.ReadInt 32(pNativeData) ;
return DDModelCache.In stance.GetModel (id);
}

public System.IntPtr MarshalManagedT oNative(object managedObj)
{
IDataDrivenMode l ddModel = (IDataDrivenMod el)managedObj;
IntPtr unmanagedArray = Marshal.AllocHG lobal(sizeof(In t32));
Marshal.WriteIn t32(unmanagedAr ray, ddModel.ID);
return unmanagedArray;
}

public void CleanUpManagedD ata(object ManagedObj)
{
}

public int GetNativeDataSi ze()
{
return sizeof(Int32);
}

public void CleanUpNativeDa ta(System.IntPt r pNativeData)
{
Marshal.FreeHGl obal(pNativeDat a);
}
}