如何使用 ctypes 將 SendInput function 包裝到 python

Question

I am trying to get the SendInput function from user32.dll to work in python using ctypes.I am a noob but from what I read from the docs you have to create the structs the function requires in python and then pass it to the function.

import ctypes
import keyboard
from ctypes import *
lib = windll.user32

KEYEVENTF_SCANCODE = 0x8
KEYEVENTF_KEYUP = 0x2
SPACEBAR = 57 # 0x39
INPUT_KEYBOARD = 1


class KEYBDINPUT(Structure):
    _fields_ = [('wVk' , c_ushort) , ('wScan' , c_ushort)
    , ('dwFlags' , c_ulong) , ('time' , c_ulong) , ('dwExtraInfo' , c_ulong)]
class INPUT(Structure):
    _fields_ = [('type' , c_ulong) ,('ki' , KEYBDINPUT)]


lib.SendInput.restype = c_uint
lib.SendInput.argtypes = [c_uint , INPUT , c_int]

keybdinput_obj = KEYBDINPUT(0 , SPACEBAR , KEYEVENTF_SCANCODE , 0 , 0)
input_obj = INPUT(INPUT_KEYBOARD , keybdinput_obj)
keyboard.wait('u')
lib.SendInput(1 , byref(input_obj) , sizeof(INPUT))
keybdinput_obj = KEYBDINPUT(0 , SPACEBAR , KEYEVENTF_SCANCODE | KEYEVENTF_KEYUP , 0 , 0)
input_obj = INPUT(INPUT_KEYBOARD , keybdinput_obj)
lib.SendInput(1 , byref(input_obj) , sizeof(INPUT))

在我從 INPUT 結構引導自己的微軟文檔中，有一個聯合，但我想如果我只需要 KEYBDINPUT 那么它就像我有一個聯合一樣。

https://docs.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-input

https://docs.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-keybdinput

https://docs.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-sendinput

我幾乎被卡住了，因為我看不出這里出了什么問題，所以我尋求幫助。程序應該在我按鍵盤上的“u”后發送一個空格（這是出於調試目的），我這樣做了這樣是因為我希望它作為掃描碼而不是虛擬按鍵發送。

因此，如果在 python 中有另一種方法可以發送掃描碼，那將很有效，我將不勝感激。

Answer 1

定義整個聯合，或者至少是 MOUSEINPUT，它是聯合的最大成員。 您可以通過 print(sizeof(INPUT)) 測試您的定義是否正確，並且它應該與在 C 程序中打印 INPUT 結構的大小一致。 我得到了 32 位的 28 號和 64 位 C 結構的 40 號。

此外，SendInput 的第二個參數是 POINTER(INPUT)，而不是 INPUT，並且 ULONG_PTR 不一定是c_ulong ，因為它取決於運行 32 位或 64 位 Python。

這是一個經過測試的示例：

import ctypes
from ctypes import *
from ctypes import wintypes as w

KEYEVENTF_SCANCODE = 0x8
KEYEVENTF_UNICODE = 0x4
KEYEVENTF_KEYUP = 0x2
SPACE = 0x39
INPUT_KEYBOARD = 1

# not defined by wintypes
ULONG_PTR = c_ulong if sizeof(c_void_p) == 4 else c_ulonglong

class KEYBDINPUT(Structure):
    _fields_ = [('wVk' ,w.WORD),
                ('wScan',w.WORD),
                ('dwFlags',w.DWORD),
                ('time',w.DWORD),
                ('dwExtraInfo',ULONG_PTR)]

class MOUSEINPUT(Structure):
    _fields_ = [('dx' ,w.LONG),
                ('dy',w.LONG),
                ('mouseData',w.DWORD),
                ('dwFlags',w.DWORD),
                ('time',w.DWORD),
                ('dwExtraInfo',ULONG_PTR)]

class HARDWAREINPUT(Structure):
    _fields_ = [('uMsg' ,w.DWORD),
                ('wParamL',w.WORD),
                ('wParamH',w.WORD)]

class DUMMYUNIONNAME(Union):
    _fields_ = [('mi',MOUSEINPUT),
                ('ki',KEYBDINPUT),
                ('hi',HARDWAREINPUT)] 

class INPUT(Structure):
    _anonymous_ = ['u']
    _fields_ = [('type',w.DWORD),
                ('u',DUMMYUNIONNAME)]

print(sizeof(INPUT))

lib = WinDLL('user32')
lib.SendInput.argtypes = w.UINT,POINTER(INPUT),c_int
lib.SendInput.restype = w.UINT

def send_scancode(code):
    i = INPUT()
    i.type = INPUT_KEYBOARD
    i.ki = KEYBDINPUT(0,code,KEYEVENTF_SCANCODE,0,0)
    lib.SendInput(1,byref(i),sizeof(INPUT))
    i.ki.dwFlags |= KEYEVENTF_KEYUP
    lib.SendInput(1,byref(i),sizeof(INPUT))

def send_unicode(s):
    i = INPUT()
    i.type = INPUT_KEYBOARD
    for c in s:
        i.ki = KEYBDINPUT(0,ord(c),KEYEVENTF_UNICODE,0,0)
        lib.SendInput(1,byref(i),sizeof(INPUT))
        i.ki.dwFlags |= KEYEVENTF_KEYUP
        lib.SendInput(1,byref(i),sizeof(INPUT))

send_scancode(SPACE)
send_unicode('The quick brown fox jumped over the lazy dog')

Output 在終端上運行 64 位 Python 3.6：

C:\>example
40

C:\> The quick brown fox jumped over the lazy dog