#include <GuiComboBox.au3>
#include <GUIConstantsEx.au3>
#include <MsgBoxConstants.au3>
#include <WindowsConstants.au3>

Global $g_hCombo

Example()

Func Example()
	Local $hGUI

	; Create GUI
	$hGUI = GUICreate("(UDF) ComboBox Create", 400, 296)
	$g_hCombo = _GUICtrlComboBox_Create($hGUI, "", 2, 2, 396, 296)
	GUISetState(@SW_SHOW)

	; Add files
	_GUICtrlComboBox_BeginUpdate($g_hCombo)
	_GUICtrlComboBox_AddDir($g_hCombo, "", $DDL_DRIVES, False)
	_GUICtrlComboBox_EndUpdate($g_hCombo)

	GUIRegisterMsg($WM_COMMAND, "WM_COMMAND")

	; Loop until the user exits.
	Do
	Until GUIGetMsg() = $GUI_EVENT_CLOSE
	GUIDelete()
EndFunc   ;==>Example

Func WM_COMMAND($hWnd, $iMsg, $wParam, $lParam)
	#forceref $hWnd, $iMsg
	Local $hWndFrom, $iIDFrom, $iCode
	$hWndFrom = $lParam
	$iIDFrom = BitAND($wParam, 0xFFFF) ; Low Word
	$iCode = BitShift($wParam, 16) ; Hi Word
	Switch $hWndFrom
		Case $g_hCombo
			Switch $iCode
				Case $CBN_CLOSEUP ; Sent when the list box of a combo box has been closed
					MsgBox(0,"","$CBN_CLOSEUP")
				Case $CBN_DBLCLK ; Sent when the user double-clicks a string in the list box of a combo box
					MsgBox(0,"","$CBN_DBLCLK")
				Case $CBN_DROPDOWN ; Sent when the list box of a combo box is about to be made visible
					MsgBox(0,"","$CBN_DROPDOWN")
				Case $CBN_EDITCHANGE ; Sent after the user has taken an action that may have altered the text in the edit control portion of a combo box
					MsgBox(0,"","$CBN_EDITCHANGE")
				Case $CBN_EDITUPDATE ; Sent when the edit control portion of a combo box is about to display altered text

				Case $CBN_ERRSPACE ; Sent when a combo box cannot allocate enough memory to meet a specific request

				Case $CBN_KILLFOCUS ; Sent when a combo box loses the keyboard focus

				Case $CBN_SELCHANGE ; Sent when the user changes the current selection in the list box of a combo box
					MsgBox(0,"","$CBN_SELCHANGE")

			EndSwitch
	EndSwitch
	Return $GUI_RUNDEFMSG
EndFunc   ;==>WM_COMMAND