Import Multiple DLL's?

I wonder if there's anyway to import multiple DLL's, or Use this:

<DllImport("Exemple.dll")> Public Shared Sub Main()
And replece "Exemple.dll by a variable.

I'm trying to do a program like this:

For Each file In My.Computer.FileSystem.GetFiles(Dir, FileIO.SearchOption.SearchTopLevelOnly)
ListBox1.Items.Add(My.Computer.FileSystem.GetFileInfo(file).Name & ".dll")
Next

In this case, Dir contains DLL files. I want that when the user double click on an item in Listbox1, it import the dll file with the same name as the item.text