keyboard.py

"""
Source from Stack Overflow:
http://stackoverflow.com/questions/13564851/generate-keyboard-events
"""

import ctypes
from ctypes import wintypes
import time

user32 = ctypes.WinDLL('user32', use_last_error=True)

INPUT_MOUSE    = 0
INPUT_KEYBOARD = 1
INPUT_HARDWARE = 2

KEYEVENTF_EXTENDEDKEY = 0x0001
KEYEVENTF_KEYUP       = 0x0002
KEYEVENTF_UNICODE     = 0x0004
KEYEVENTF_SCANCODE    = 0x0008

MAPVK_VK_TO_VSC = 0

# msdn.microsoft.com/en-us/library/dd375731
VK_CONTROL = 0x11
VK_MENU = 0x12
VK_LEFT = 0x25
VK_UP = 0x26
VK_RIGHT = 0x27
VK_DOWN = 0x28
VK_F10 = 0x79
VK_F11 = 0x7A
VK_F12 = 0x7B

# C struct definitions

wintypes.ULONG_PTR = wintypes.WPARAM

class MOUSEINPUT(ctypes.Structure):
    _fields_ = (("dx",          wintypes.LONG),
                ("dy",          wintypes.LONG),
                ("mouseData",   wintypes.DWORD),
                ("dwFlags",     wintypes.DWORD),
                ("time",        wintypes.DWORD),
                ("dwExtraInfo", wintypes.ULONG_PTR))

class KEYBDINPUT(ctypes.Structure):
    _fields_ = (("wVk",         wintypes.WORD),
                ("wScan",       wintypes.WORD),
                ("dwFlags",     wintypes.DWORD),
                ("time",        wintypes.DWORD),
                ("dwExtraInfo", wintypes.ULONG_PTR))

    def __init__(self, *args, **kwds):
        super(KEYBDINPUT, self).__init__(*args, **kwds)
        # some programs use the scan code even if KEYEVENTF_SCANCODE
        # isn't set in dwFflags, so attempt to map the correct code.
        if not self.dwFlags & KEYEVENTF_UNICODE:
            self.wScan = user32.MapVirtualKeyExW(self.wVk,
                                                 MAPVK_VK_TO_VSC, 0)

class HARDWAREINPUT(ctypes.Structure):
    _fields_ = (("uMsg",    wintypes.DWORD),
                ("wParamL", wintypes.WORD),
                ("wParamH", wintypes.WORD))

class INPUT(ctypes.Structure):
    class _INPUT(ctypes.Union):
        _fields_ = (("ki", KEYBDINPUT),
                    ("mi", MOUSEINPUT),
                    ("hi", HARDWAREINPUT))
    _anonymous_ = ("_input",)
    _fields_ = (("type",   wintypes.DWORD),
                ("_input", _INPUT))

LPINPUT = ctypes.POINTER(INPUT)

def _check_count(result, func, args):
    if result == 0:
        raise ctypes.WinError(ctypes.get_last_error())
    return args

user32.SendInput.errcheck = _check_count
user32.SendInput.argtypes = (wintypes.UINT, # nInputs
                             LPINPUT,       # pInputs
                             ctypes.c_int)  # cbSize

# Functions

def PressKey(hexKeyCode):
    x = INPUT(type=INPUT_KEYBOARD,
              ki=KEYBDINPUT(wVk=hexKeyCode))
    user32.SendInput(1, ctypes.byref(x), ctypes.sizeof(x))

def ReleaseKey(hexKeyCode):
    x = INPUT(type=INPUT_KEYBOARD, ki=KEYBDINPUT(wVk=hexKeyCode, dwFlags=KEYEVENTF_KEYUP))
    user32.SendInput(1, ctypes.byref(x), ctypes.sizeof(x))

# Key combinations
def CtrlAltPress():  # generic
    PressKey(VK_CONTROL)
    PressKey(VK_MENU)

def CtrlAltRelease():  # generic
    ReleaseKey(VK_CONTROL)
    ReleaseKey(VK_MENU)

def CtrlAltRight():
    CtrlAltPress()
    PressKey(VK_RIGHT)
    ReleaseKey(VK_RIGHT)
    CtrlAltRelease()

def CtrlAltLeft():
    CtrlAltPress()
    PressKey(VK_LEFT)
    ReleaseKey(VK_LEFT)
    CtrlAltRelease()

def CtrlAltUp():
    CtrlAltPress()
    PressKey(VK_UP)
    ReleaseKey(VK_UP)
    CtrlAltRelease()

def CtrlAltDown():
    CtrlAltPress()
    PressKey(VK_DOWN)
    ReleaseKey(VK_DOWN)
    CtrlAltRelease()

def CtrlAltF10():
    CtrlAltPress()
    PressKey(VK_F10)
    ReleaseKey(VK_F10)
    CtrlAltRelease()

def CtrlAltF11():
    CtrlAltPress()
    PressKey(VK_F11)
    ReleaseKey(VK_F11)
    CtrlAltRelease()

def CtrlAltF12():
    CtrlAltPress()
    PressKey(VK_F12)
    ReleaseKey(VK_F12)
    CtrlAltRelease()