Active Directory and .NET : paging the search result

Question

Hi everybody!

I have a question about Active Directory in .NET
For my project I need to fetch results from Active Directory search page by page, because later I would need to bind it to the pageable DataGrid.

I tried to use .NET library DirectoryServices for that, but paging provided by this library is transparent to the user and is used only to increase the efficiency of searching, when results are too big. I.e. I cannot tell the DirectorySearcher to give me first page, then the next or previous page, it returns me all resulting pages in one bundle.

However, what I need is to explicitely get page after page directly from the AD searcher and to be able to go at least one page forward or backward.

The solution with copying all results to the DataBase and then do the paging is not accepeted by the clent, since it is too inefficient. And since it's a Web app, I cannot keep results in memory either.

I found some hints about COM Interface, but I could not find good and detailed examples or explanations. I found also axample with this code: 
DirectoryServices.Interop.IDirectorySearch.ExecuteSearch ()
but I can't find which library should i include to be able to compile this code.

If somebody could help me out with that problem, any suggestion is welcome, 'cause this issue is eating me alive :)

Thank you!