Retrieve the number of columns
#include <GuiListView.au3>
_GUICtrlListView_GetColumnCount ( $hWnd )
| $hWnd | Control ID/Handle to the control | 
#include <GUIConstantsEx.au3>
#include <GuiListView.au3>
#include <MsgBoxConstants.au3>
Example()
Func Example()
    Local $idListview
    GUICreate("ListView Get Column Count", 400, 300)
    $idListview = GUICtrlCreateListView("col1|col2|col3", 2, 2, 394, 268)
    GUISetState(@SW_SHOW)
    MsgBox($MB_SYSTEMMODAL, "Information", "Column Count: " & _GUICtrlListView_GetColumnCount($idListview))
    ; Loop until the user exits.
    Do
    Until GUIGetMsg() = $GUI_EVENT_CLOSE
    GUIDelete()
EndFunc   ;==>Example