VS 2010 Help:for each loop and for next loop

Hi,
i am looking to display folders of a particular directory in a listbox.

below is the code for the same using 'for each loop'

Private Sub btnForEachLoop_Click(sender As Object, e As EventArgs) Handles btnForEachLoop.Click

'Clearlist
Clearlist()

'List each folder of root of C: drive
For each srtFolder As string in
My.Computer.FileSystem.GetDirectories("C:\")

'add items in listbox
lstData.Items.Add(srtFolder)
Next

End Sub
End Class


MY QUERY:- HOW CAN I PERFORM THE SAME OPERATION USING 'FOR NEXT LOOP'

Below is what i did so far



Private Sub btnFornextLoop_Click(sender As Object, e As EventArgs) Handles btnForNextLoop.Click

'declare variables
Dim Counter As System.Collections.ObjectModel.ReadOnlyCollection(Of String)
Dim intStep As Integer

Counter = My.Computer.FileSystem.GetDirectories("C:\")

'Clear list
Clearlist()

'List each folder at root of C: drive
For intStep = 1 To Counter.Count

'list and add items in listbox
lstData.Items.Add(My.Computer.FileSystem.GetDirectories("C:\"))
Next

End Sub
End Class

but in list box i am getting

(collection)
(collection)

....
instead of folder names.