NT user access permission to folders and files

Hi there
I'm developing an intranet site using ASP. In this project I need to list all the available folders and files that the currently logged on user has acess to.

My problem is how i can get ACL information on a folder or file. I need to know what kind of access authority the current user has (for example, read, write, change, deny delete etc) on a particular folder or file.

I have heard that using ADSI I can solve this. But i didn't find any reference.

Can anyone help me?

Thanks in advance

Mahfooz