Code:
Option Explicit

Private Sub Command1_Click()
MsgBox "there are " &  List1.ListCount & " items in the listbox"
MsgBox List1.List(List1.ListIndex) 'the currently selected item
End Sub

Private Sub Form_Load()
Dim i As Integer

For i = 0 To 10
  List1.AddItem "item " & i

Next i
End Sub