Reference to ArcObjects IUknown interface

Question

Does anyone know what the ArcObjects reference library is for the IUnknown interface? I migrated the code below into Visual Studio and there is an error on the "Dim pSelItem As IUnknown" line.

ERROR 'IUknown' is not accessible in the context because it is 'Friend'

' Get the selected layer or table
        Dim pTable As ITable
        Dim pDispTab As IDisplayTable
        Dim pStAloneTab As IStandaloneTable
        Dim pSelItem As IUnknown
        pSelItem = m_pMxDoc2.SelectedItem 

I'm guessing I need to provide the full path reference for the Dim line? Maybe there is a newer interface that I can assign pSelItem to for .NET?

UPDATE:

Maybe it should be "Dim pSelItem as Object", since the IMxDocument.SelectedItem Property for .NET accepts Object?

IMxDocument.SelectedItem Property link

Answer 1

You rarely need to access IUnknown in day-to-day AO development (or COM interop for that matter). Declaring your variable as object will do the trick since you will anyway need to cast it to another interface afterwards.