所以我想弄清楚如何使用 Python 注册一个全局键盘钩子。根据我的阅读,在 DLL 中没有回调似乎是可以的。如果你使用 WH_KEYBOARD_LL。我不能肯定地确认这一点,但我发现令人鼓舞的是,如果我尝试挂钩说
WH_CBT
.,我不会像我那样收到 1428 错误
我得到了一个钩形手柄,但是当我按下键盘上的按钮时没有任何显示,正如我所期望的那样。
知道为什么我的回调没有被调用吗?或者这甚至可能吗?
相关代码:
import time
import string
import ctypes
import functools
import atexit
import pythoncom
from ctypes import windll
hookID = 0
class Keyboard(object):
KEY_EVENT_DOWN = 0
KEY_EVENT_UP = 2
KEY_ENTER = 2
KEY_SHIFT = 16
KEY_SPACE = 32
HOOK_ACTION = 13
HOOK_KEYBOARD = 13
HOOK_KEYDOWN = 0x100
HOOK_KEYUP = 0x101
class Hook:
'''Holds general hook information'''
def __init__(self):
self.hook = 0
self.struct = None
class HookStruct(ctypes.Structure):
'''Structure that windows returns for keyboard events'''
__fields__ = [
('keycode', ctypes.c_long),
('scancode', ctypes.c_long),
('flags', ctypes.c_long),
('time', ctypes.c_long),
('info', ctypes.POINTER(ctypes.c_ulong))
]
def ascii_to_keycode(self, char):
return windll.user32.VkKeyScanA(ord(char))
def inject_key_down(self, keycode):
scancode = windll.user32.MapVirtualKeyA(keycode, 0)
windll.user32.keybd_event(keycode, scancode, Keyboard.KEY_EVENT_DOWN, 0)
def inject_key_up(self, keycode):
scan = windll.user32.MapVirtualKeyA(keycode, 0)
windll.user32.keybd_event(keycode, scan, Keyboard.KEY_EVENT_UP, 0)
def inject_key_press(self, keycode, pause=0.05):
self.inject_key_down(keycode)
time.sleep(pause)
self.inject_key_up(keycode)
def inject_sequence(self, seq, pause=0.05):
for key in seq:
if key == ' ':
self.inject_key_press(Keyboard.KEY_SPACE, pause)
elif key == '\n':
self.inject_key_press(Keyboard.KEY_ENTER, pause)
else:
if key in string.ascii_uppercase:
self.inject_key_down(Keyboard.KEY_SHIFT)
self.inject_key_press(self.ascii_to_keycode(key), pause)
self.inject_key_up(Keyboard.KEY_SHIFT)
else:
self.inject_key_press(self.ascii_to_keycode(key), pause)
def _win32_copy_mem(self, dest, src):
src = ctypes.c_void_p(src)
windll.kernel32.RtlMoveMemory(ctypes.addressof(dest), src, ctypes.sizeof(dest))
def _win32_get_last_error(self):
return windll.kernel32.GetLastError()
def _win32_get_module(self, mname):
return windll.kernel32.GetModuleHandleA(mname)
def _win32_call_next_hook(self, id, code, wparam, lparam):
return windll.kernel32.CallNextHookEx(id, code, wparam, lparam)
def _win32_set_hook(self, id, callback, module, thread):
callback_decl = ctypes.WINFUNCTYPE(ctypes.c_long, ctypes.c_long, ctypes.c_long, ctypes.c_long)
return windll.user32.SetWindowsHookExA(id, callback_decl(callback), module, thread)
def _win32_unhook(self, id):
return windll.user32.UnhookWindowsHookEx(id)
def keyboard_event(self, data):
print data.scancode
return False
def capture_input(self):
self.hook = Keyboard.Hook()
self.hook.struct = Keyboard.HookStruct()
def low_level_keyboard_proc(code, event_type, kb_data_ptr):
# win32 spec says return result of CallNextHookEx if code is less than 0
if code < 0:
return self._win32_call_next_hook(self.hook.hook, code, event_type, kb_data_ptr)
if code == Keyboard.HOOK_ACTION:
# copy data from struct into Python structure
self._win32_copy_mem(self.hook.struct, kb_data_ptr)
# only call other handlers if we return false from our handler - allows to stop processing of keys
if self.keyboard_event(self.hook.struct):
return self._win32_call_next_hook(self.hook.hook, code, event_type, kb_data_ptr)
# register hook
try:
hookId = self.hook.hook = self._win32_set_hook(Keyboard.HOOK_KEYBOARD, low_level_keyboard_proc, self._win32_get_module(0), 0)
if self.hook.hook == 0:
print 'Error - ', self._win32_get_last_error()
else:
print 'Hook ID - ', self.hook.hook
except Exception, error:
print error
# unregister hook if python exits
atexit.register(functools.partial(self._win32_unhook, self.hook.hook))
def end_capture(self):
if self.hook.hook:
return self._win32_unhook(self.hook.hook)
kb = Keyboard()#kb.inject_sequence('This is a test\nand tHis is line 2')
kb.capture_input()
pythoncom.PumpMessages()
kb.end_capture()
我无法让你的班级工作,但我在这个帖子中找到了实现相同目标的类似方法.
这里是修改后的代码:
from collections import namedtuple
KeyboardEvent = namedtuple('KeyboardEvent', ['event_type', 'key_code',
'scan_code', 'alt_pressed',
'time'])
handlers = []
def listen():
"""
Calls `handlers` for each keyboard event received. This is a blocking call.
"""
# Adapted from http://www.hackerthreads.org/Topic-42395
from ctypes import windll, CFUNCTYPE, POINTER, c_int, c_uint, c_void_p, byref
import win32con, win32api, win32gui, atexit
event_types = {win32con.WM_KEYDOWN: 'key down',
win32con.WM_KEYUP: 'key up',
0x104: 'key down', # WM_SYSKEYDOWN, used for Alt key.
0x105: 'key up', # WM_SYSKEYUP, used for Alt key.
}
def low_level_handler(nCode, wParam, lParam):
"""
Processes a low level Windows keyboard event.
"""
event = KeyboardEvent(event_types[wParam], lParam[0], lParam[1],
lParam[2] == 32, lParam[3])
for handler in handlers:
handler(event)
# Be a good neighbor and call the next hook.
return windll.user32.CallNextHookEx(hook_id, nCode, wParam, lParam)
# Our low level handler signature.
CMPFUNC = CFUNCTYPE(c_int, c_int, c_int, POINTER(c_void_p))
# add argtypes for 64-bit Python compatibility (per @BaiJiFeiLong)
windll.user32.SetWindowsHookExW.argtypes = (
c_int,
c_void_p,
c_void_p,
c_uint
)
# Convert the Python handler into C pointer.
pointer = CMPFUNC(low_level_handler)
# Hook both key up and key down events for common keys (non-system).
hook_id = windll.user32.SetWindowsHookExA(win32con.WH_KEYBOARD_LL, pointer,
win32api.GetModuleHandle(None), 0)
# Register to remove the hook when the interpreter exits. Unfortunately a
# try/finally block doesn't seem to work here.
atexit.register(windll.user32.UnhookWindowsHookEx, hook_id)
while True:
msg = win32gui.GetMessage(None, 0, 0)
win32gui.TranslateMessage(byref(msg))
win32gui.DispatchMessage(byref(msg))
if __name__ == '__main__':
def print_event(e):
print(e)
handlers.append(print_event)
listen()
keyboard
.
Tim原来的代码没有运行的原因是因为指向
low_level_keyboard_proc
的ctypes函数指针被垃圾回收了,所以他的回调就失效了,没有被调用。它只是默默地失败了。
Windows 不保留 Python 指针,因此我们需要单独保留对传递给 SetWindowsHookEx 的确切
callback_decl(callback)
ctypes 函数指针参数的引用。
我还没有专门用 Python 尝试过,但是是的,它应该可以用于低级键盘或鼠标钩子。对于其他类型的钩子,钩子函数必须在dll中。
HOOK_ACTION 应该是 0,而不是 13。