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

MsgBox(4096, "", Example())

Func Example()
    Local $hWnd = GUICreate("InputBox", 300, 75, -1, -1, -1, $WS_EX_TOPMOST)
    Local $iInput = GUICtrlCreateInput("", 5, 5, 290, 20)
    Local $iClose = GUICtrlCreateButton("&OK", 300 - 90, 75 - 30, 85, 25)

    GUISetState(@SW_SHOW, $hWnd)

    While 1
        Switch GUIGetMsg()
            Case $GUI_EVENT_CLOSE, $iClose
                ExitLoop

        EndSwitch
    WEnd
    Local $sReturn = GUICtrlRead($iInput)
    GUIDelete($hWnd)
    Return $sReturn
EndFunc   ;==>Example