如何在Pynput的on_pressed/on_release处理器中检测Ctrl、Shift或Alt是否按下？

当然可以，Pynput提供了两种实用方式实现这个需求：

方式一：通过键盘控制器实时查询按键状态 #

使用keyboard.Controller()的pressed()方法，能在事件处理器中直接查询指定按键的按下状态。

示例代码：

from pynput import keyboard

def on_press(key):
    # 初始化键盘控制器
    controller = keyboard.Controller()
    
    # 检测Ctrl键（包含左右Ctrl）
    ctrl_pressed = keyboard.Key.ctrl in controller.pressed()
    # 检测Shift键
    shift_pressed = keyboard.Key.shift in controller.pressed()
    # 检测Alt键
    alt_pressed = keyboard.Key.alt in controller.pressed()
    
    print(f"Ctrl: {ctrl_pressed}, Shift: {shift_pressed}, Alt: {alt_pressed}")
    
    # 按Esc键退出监听
    if key == keyboard.Key.esc:
        return False

def on_release(key):
    pass

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

方式二：手动跟踪按键状态 #

维护一个集合记录当前按下的按键，在on_press和on_release事件中更新集合，之后直接查询集合即可。这种方式无需重复创建控制器，性能更优。

示例代码：

from pynput import keyboard

# 存储当前按下的按键
pressed_keys = set()

def on_press(key):
    pressed_keys.add(key)
    
    # 检测组合键状态（区分左右按键）
    ctrl_pressed = keyboard.Key.ctrl in pressed_keys or keyboard.Key.ctrl_l in pressed_keys or keyboard.Key.ctrl_r in pressed_keys
    shift_pressed = keyboard.Key.shift in pressed_keys or keyboard.Key.shift_l in pressed_keys or keyboard.Key.shift_r in pressed_keys
    alt_pressed = keyboard.Key.alt in pressed_keys or keyboard.Key.alt_l in pressed_keys or keyboard.Key.alt_r in pressed_keys
    
    print(f"Ctrl: {ctrl_pressed}, Shift: {shift_pressed}, Alt: {alt_pressed}")
    
    if key == keyboard.Key.esc:
        return False

def on_release(key):
    if key in pressed_keys:
        pressed_keys.remove(key)

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

如果需要精准区分左右按键（比如左Ctrl和右Ctrl），直接判断keyboard.Key.ctrl_l或keyboard.Key.ctrl_r这类具体按键即可。

内容的提问来源于stack exchange，提问作者fmatz