如何使用python中的ctypes获取Windows窗口名称

我尝试通过长对象的句柄来获得Windows窗口标题名称和pid。 我的代码工作,但有一些问题。 当我得到10个或更多时,我只能获得4个窗口标题。 任何人都可以帮助,并告诉我如何解决这个代码? 我认为问题在于如何转换长对象(我不太了解它们,以及一般的ctypes)。

from __future__ import print_function from ctypes import * psapi = windll.psapi titles = [] # get window title from pid def gwtfp(): max_array = c_ulong * 4096 pProcessIds = max_array() pBytesReturned = c_ulong() psapi.EnumProcesses(byref(pProcessIds), sizeof(pProcessIds), byref(pBytesReturned)) # get the number of returned processes nReturned = pBytesReturned.value/sizeof(c_ulong()) pidProcessArray = [i for i in pProcessIds][:nReturned] print(pidProcessArray) # EnumWindows = windll.user32.EnumWindows EnumWindowsProc = WINFUNCTYPE(c_bool, POINTER(c_int), POINTER(c_int)) GetWindowText = windll.user32.GetWindowTextW GetWindowTextLength = windll.user32.GetWindowTextLengthW IsWindowVisible = windll.user32.IsWindowVisible for process in pidProcessArray: #print("Process PID %d" % process) if IsWindowVisible(process): length = GetWindowTextLength(process) buff = create_unicode_buffer(length + 1) GetWindowText(process, buff, length + 1) titles.append(buff.value) gwtfp() print(titles) 

您将一个进程ID传递给带有窗口句柄的函数。 你要做的是枚举顶层窗口的句柄,然后将每个窗口映射到进程ID。

首先让我们定义ctypes函数原型,以获得函数参数的正确类型检查。 另外,使用use_last_error=True通过ctypes.get_last_error获得最安全的错误处理。 许多Windows函数返回一个错误,所以在这种情况下使用一个errcheck函数比较方便,比如check_zero

 from __future__ import print_function import ctypes from ctypes import wintypes from collections import namedtuple user32 = ctypes.WinDLL('user32', use_last_error=True) def check_zero(result, func, args): if not result: err = ctypes.get_last_error() if err: raise ctypes.WinError(err) return args if not hasattr(wintypes, 'LPDWORD'): # PY2 wintypes.LPDWORD = ctypes.POINTER(wintypes.DWORD) WindowInfo = namedtuple('WindowInfo', 'pid title') WNDENUMPROC = ctypes.WINFUNCTYPE( wintypes.BOOL, wintypes.HWND, # _In_ hWnd wintypes.LPARAM,) # _In_ lParam user32.EnumWindows.errcheck = check_zero user32.EnumWindows.argtypes = ( WNDENUMPROC, # _In_ lpEnumFunc wintypes.LPARAM,) # _In_ lParam user32.IsWindowVisible.argtypes = ( wintypes.HWND,) # _In_ hWnd user32.GetWindowThreadProcessId.restype = wintypes.DWORD user32.GetWindowThreadProcessId.argtypes = ( wintypes.HWND, # _In_ hWnd wintypes.LPDWORD,) # _Out_opt_ lpdwProcessId user32.GetWindowTextLengthW.errcheck = check_zero user32.GetWindowTextLengthW.argtypes = ( wintypes.HWND,) # _In_ hWnd user32.GetWindowTextW.errcheck = check_zero user32.GetWindowTextW.argtypes = ( wintypes.HWND, # _In_ hWnd wintypes.LPWSTR, # _Out_ lpString ctypes.c_int,) # _In_ nMaxCount 

这是一个列出可见窗口的函数。 它使用一个回调,而不是使用可选的lParam参数,而不是result 。 后者将需要投下论据。 使用闭包更简单。

 def list_windows(): '''Return a sorted list of visible windows.''' result = [] @WNDENUMPROC def enum_proc(hWnd, lParam): if user32.IsWindowVisible(hWnd): pid = wintypes.DWORD() tid = user32.GetWindowThreadProcessId( hWnd, ctypes.byref(pid)) length = user32.GetWindowTextLengthW(hWnd) + 1 title = ctypes.create_unicode_buffer(length) user32.GetWindowTextW(hWnd, title, length) result.append(WindowInfo(pid.value, title.value)) return True user32.EnumWindows(enum_proc, 0) return sorted(result) 

为了完整性,这里有一个列出所有进程ID的函数。 这包括属于其他Windows会话的进程(例如会话0中的服务)。

 psapi = ctypes.WinDLL('psapi', use_last_error=True) psapi.EnumProcesses.errcheck = check_zero psapi.EnumProcesses.argtypes = ( wintypes.LPDWORD, # _Out_ pProcessIds wintypes.DWORD, # _In_ cb wintypes.LPDWORD,) # _Out_ pBytesReturned def list_pids(): '''Return sorted list of process IDs.''' length = 4096 PID_SIZE = ctypes.sizeof(wintypes.DWORD) while True: pids = (wintypes.DWORD * length)() cb = ctypes.sizeof(pids) cbret = wintypes.DWORD() psapi.EnumProcesses(pids, cb, ctypes.byref(cbret)) if cbret.value < cb: length = cbret.value // PID_SIZE return sorted(pids[:length]) length *= 2 

例如:

 if __name__ == '__main__': print('Process IDs:') print(*list_pids(), sep='\n') print('\nWindows:') print(*list_windows(), sep='\n') 

MSDN链接:

  • EnumWindows
  • IsWindowVisible
  • GetWindowThreadProcessId
  • GetWindowTextLength
  • GetWindowText
  • EnumProcesses