How to generate keyboard events?
short summary:
I am trying to create a program that will send keyboard events to the computer that for all purposes the simulated events should be treated as actual keystrokes on the keyboard.
original post:
I am looking for a way to generate keyboard events using python.
Assume that the function receives a key that it must simulate pressing, like so:
keyboardevent('a') #lower case 'a'
keyboardevent('B') #upper case 'B'
keyboardevent('->') # right arrow key
def keyboardevent(key):
#code that simulated 'key' being pressed on keyboard
The above are obviously examples, but what I am looking for is a library, module, or whatever, which I can use to simulate keyboard events.
note: This is different than sending characters to notepads, or inputting text into fields or such. I want the python script to simulate an actual keyboard event, the computer will think that there is really a keyboard event.
Extra Note:
I don't want to send keystrokes to the active window - I want the system to believe the keyboard's keys are being pressed, subtle difference, as some active-windows do not accept certain key-combinations, or if I wanted to use keyboard shortcuts for background processes through my script, they don't need to go through the active-window
So far I have looked at these things:
Generate keyboard events for the frontmost application
How to generate keyboard keypress events through Python?
Which were all about apple and didn't help at all.
And this:
Which is the easiest way to simulate keyboard and mouse on Python?
Which seems like it might be what I need, but I can not find the library for it or any documentation.
I have searched more places as well, but have yet to find a solution.
Solution 1:
It can be done using ctypes:
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_TAB = 0x09
VK_MENU = 0x12
# 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))
def AltTab():
"""Press Alt+Tab and hold Alt key for 2 seconds
in order to see the overlay.
"""
PressKey(VK_MENU) # Alt
PressKey(VK_TAB) # Tab
ReleaseKey(VK_TAB) # Tab~
time.sleep(2)
ReleaseKey(VK_MENU) # Alt~
if __name__ == "__main__":
AltTab()
hexKeyCode is the virtual keyboard mapping as defined by the Windows API. The list of codes is available on MSDN: Virtual-Key Codes (Windows)
Solution 2:
For both python3 and python2 you can use pyautogui (pip install pyautogui)
from pyautogui import press, typewrite, hotkey
press('a')
typewrite('quick brown fox')
hotkey('ctrl', 'w')
It's also crossplatform with Windows, OSX, and Ubuntu LTS.
Solution 3:
user648852's idea at least for me works great for OS X, here is the code to do it:
#!/usr/bin/env python
import time
from Quartz.CoreGraphics import CGEventCreateKeyboardEvent
from Quartz.CoreGraphics import CGEventPost
# Python releases things automatically, using CFRelease will result in a scary error
#from Quartz.CoreGraphics import CFRelease
from Quartz.CoreGraphics import kCGHIDEventTap
# From http://stackoverflow.com/questions/281133/controlling-the-mouse-from-python-in-os-x
# and from https://developer.apple.com/library/mac/documentation/Carbon/Reference/QuartzEventServicesRef/index.html#//apple_ref/c/func/CGEventCreateKeyboardEvent
def KeyDown(k):
keyCode, shiftKey = toKeyCode(k)
time.sleep(0.0001)
if shiftKey:
CGEventPost(kCGHIDEventTap, CGEventCreateKeyboardEvent(None, 0x38, True))
time.sleep(0.0001)
CGEventPost(kCGHIDEventTap, CGEventCreateKeyboardEvent(None, keyCode, True))
time.sleep(0.0001)
if shiftKey:
CGEventPost(kCGHIDEventTap, CGEventCreateKeyboardEvent(None, 0x38, False))
time.sleep(0.0001)
def KeyUp(k):
keyCode, shiftKey = toKeyCode(k)
time.sleep(0.0001)
CGEventPost(kCGHIDEventTap, CGEventCreateKeyboardEvent(None, keyCode, False))
time.sleep(0.0001)
def KeyPress(k):
keyCode, shiftKey = toKeyCode(k)
time.sleep(0.0001)
if shiftKey:
CGEventPost(kCGHIDEventTap, CGEventCreateKeyboardEvent(None, 0x38, True))
time.sleep(0.0001)
CGEventPost(kCGHIDEventTap, CGEventCreateKeyboardEvent(None, keyCode, True))
time.sleep(0.0001)
CGEventPost(kCGHIDEventTap, CGEventCreateKeyboardEvent(None, keyCode, False))
time.sleep(0.0001)
if shiftKey:
CGEventPost(kCGHIDEventTap, CGEventCreateKeyboardEvent(None, 0x38, False))
time.sleep(0.0001)
# From http://stackoverflow.com/questions/3202629/where-can-i-find-a-list-of-mac-virtual-key-codes
def toKeyCode(c):
shiftKey = False
# Letter
if c.isalpha():
if not c.islower():
shiftKey = True
c = c.lower()
if c in shiftChars:
shiftKey = True
c = shiftChars[c]
if c in keyCodeMap:
keyCode = keyCodeMap[c]
else:
keyCode = ord(c)
return keyCode, shiftKey
shiftChars = {
'~': '`',
'!': '1',
'@': '2',
'#': '3',
'$': '4',
'%': '5',
'^': '6',
'&': '7',
'*': '8',
'(': '9',
')': '0',
'_': '-',
'+': '=',
'{': '[',
'}': ']',
'|': '\\',
':': ';',
'"': '\'',
'<': ',',
'>': '.',
'?': '/'
}
keyCodeMap = {
'a' : 0x00,
's' : 0x01,
'd' : 0x02,
'f' : 0x03,
'h' : 0x04,
'g' : 0x05,
'z' : 0x06,
'x' : 0x07,
'c' : 0x08,
'v' : 0x09,
'b' : 0x0B,
'q' : 0x0C,
'w' : 0x0D,
'e' : 0x0E,
'r' : 0x0F,
'y' : 0x10,
't' : 0x11,
'1' : 0x12,
'2' : 0x13,
'3' : 0x14,
'4' : 0x15,
'6' : 0x16,
'5' : 0x17,
'=' : 0x18,
'9' : 0x19,
'7' : 0x1A,
'-' : 0x1B,
'8' : 0x1C,
'0' : 0x1D,
']' : 0x1E,
'o' : 0x1F,
'u' : 0x20,
'[' : 0x21,
'i' : 0x22,
'p' : 0x23,
'l' : 0x25,
'j' : 0x26,
'\'' : 0x27,
'k' : 0x28,
';' : 0x29,
'\\' : 0x2A,
',' : 0x2B,
'/' : 0x2C,
'n' : 0x2D,
'm' : 0x2E,
'.' : 0x2F,
'`' : 0x32,
'k.' : 0x41,
'k*' : 0x43,
'k+' : 0x45,
'kclear' : 0x47,
'k/' : 0x4B,
'k\n' : 0x4C,
'k-' : 0x4E,
'k=' : 0x51,
'k0' : 0x52,
'k1' : 0x53,
'k2' : 0x54,
'k3' : 0x55,
'k4' : 0x56,
'k5' : 0x57,
'k6' : 0x58,
'k7' : 0x59,
'k8' : 0x5B,
'k9' : 0x5C,
# keycodes for keys that are independent of keyboard layout
'\n' : 0x24,
'\t' : 0x30,
' ' : 0x31,
'del' : 0x33,
'delete' : 0x33,
'esc' : 0x35,
'escape' : 0x35,
'cmd' : 0x37,
'command' : 0x37,
'shift' : 0x38,
'caps lock' : 0x39,
'option' : 0x3A,
'ctrl' : 0x3B,
'control' : 0x3B,
'right shift' : 0x3C,
'rshift' : 0x3C,
'right option' : 0x3D,
'roption' : 0x3D,
'right control' : 0x3E,
'rcontrol' : 0x3E,
'fun' : 0x3F,
'function' : 0x3F,
'f17' : 0x40,
'volume up' : 0x48,
'volume down' : 0x49,
'mute' : 0x4A,
'f18' : 0x4F,
'f19' : 0x50,
'f20' : 0x5A,
'f5' : 0x60,
'f6' : 0x61,
'f7' : 0x62,
'f3' : 0x63,
'f8' : 0x64,
'f9' : 0x65,
'f11' : 0x67,
'f13' : 0x69,
'f16' : 0x6A,
'f14' : 0x6B,
'f10' : 0x6D,
'f12' : 0x6F,
'f15' : 0x71,
'help' : 0x72,
'home' : 0x73,
'pgup' : 0x74,
'page up' : 0x74,
'forward delete' : 0x75,
'f4' : 0x76,
'end' : 0x77,
'f2' : 0x78,
'page down' : 0x79,
'pgdn' : 0x79,
'f1' : 0x7A,
'left' : 0x7B,
'right' : 0x7C,
'down' : 0x7D,
'up' : 0x7E
}
Solution 4:
I tried lib keyboard and it works good on Windows, Mac and Linux. Below line helps me switch tabs in browser:
keyboard.press_and_release('ctrl+tab')