Comparing a KeyCode object to string in python

Question

I'm trying to trigger functions on key presses in python. I'm using the pynput library's listen function, which returns a Keycode object. I've tried casting the object to string but the following code still returns the following output (when pressing the 'a' key):

def on_press(key):
    mod = str(key)
    print(mod)
    print(type(mod))
    print(mod=='a')

I get:

'a'
< class 'str'>
False

Please take a look at this answer. [https://stackoverflow.com/questions/575650/how-to-obtain-the-keycodes-in-python](https://stackoverflow.com/questions/575650/how-to-obtain-the-keycodes-in-python) — Vignesh Krishnan, Jan 23 '19 at 05:29
Good minimal, weird example. Are you using this as written? or comparing the string to the keycode object directly? — mcint, Jan 23 '19 at 05:37

atline · Accepted Answer · 2019-01-23T05:46:03.827

Use next:

def on_press(key):
    print(key.char=='a')

Above will print True.

Your code cannot work just because:

mod = str(key)
print(mod)

Will get 'a', but for a normal string, print('a') will just print a, they are not the same string. You can confirm it with print(len(mod)) & print(len('a'))

BTW, next is a full code for your test:

from pynput.keyboard import Key, Listener
import sys

def on_press(key):
    mod = str(key)
    print(mod)
    print(type(mod))
    print(mod=='a')
    print(key.char=='a')
    print(len(mod))
    print(len('a'))
    sys.exit(0)

def on_release(key):
    pass

with Listener(on_press=on_press, on_release=on_release) as listener:
    listener.join()

Comparing a KeyCode object to string in python

1 Answers1