求助 ! 不知為什麼錯誤

tcpuuu

GUICreate("Hello World", 200, 100)
GUICtrlCreateLabel("Hello world! How are you?", 30, 10)
$okbutton = GUICtrlCreateButton("OK", 70, 50, 60)
GUISetState(@SW_SHOW)
While 1
  $msg = GUIGetMsg()
  Select
    Case $msg = $okbutton
      MsgBox(0, "GUI Event", "You pressed OK!")
    Case $msg = $GUI_EVENT_CLOSE
      MsgBox(0, "GUI Event", "You clicked CLOSE! Exiting...")
      ExitLoop
  EndSelect
WEnd


是否要加這一行?
#include <GUIConstantsEx.au3>   這一行是什麼意思?
加了也是錯?