Using the Internet Connection Sharing (ICS) and Internet Connection Firewall (ICF) COM Interfaces
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The NetworkConnectionCollection is a strongly-typed interface that is meant to simplify access to the Internet Connection Sharing and Internet Connection Firewall interfaces for each of the network connections registered on the machine.
Introduction
With the release of Windows XP's Service Pack 2, Microsoft's Internet Connection Sharing (ICS) and Internet Connection Firewall (ICF) features quickly obtained a large degree of notoriety. Many developers have been actively looking for ways to easily "peek and poke" at the ICS & ICF configurations on a given machine.
The good news is that Microsoft released the interfaces with a COM wrapper. The bad news is that it isn't well advertised and it's not very intuitive to use. Getting a full set of details on a particular connection's configuration can require several method calls.
Overview
This project contains a strongly-typed collection named NetworkConnectionCollection. When you create an instance of this collection, it automatically uses the ICS/ICF COM interfaces to iterate all of the Network Connections on the local machine and create NetworkConnection objects (as members of the NetworkConnectionCollection).
The NetworkConnection class impliments three ICS/ICF interfaces: INetConnection, INetConnectionProps and INetSharingConfiguration. When you use the ICS/ICF COM interfaces directly, you need to reference each of these independantly. By using the NetworkConnection class, you can access all of the members in one place.
Work Remaining
I haven't spent much time on this, since it does what I need at this point. One obvious improvement would be to overload a few of the members to expose/use native types (e.g. the INetConnectionProps.GUID property returns a String, but a System.Guid would be preferable). Another improvement would be to wrap the PortMappings.
References
Microsoft has exposed the API for the ICS & ICF in a couple of places, but this code uses the COM interface HNetCfg.HNetShare. You can add a reference to this interface to your own projects by using the Reference Browser to select HNETCFG.DLL (typically located in the "C:\Windows\System32\" directory).