如何在 Python 中读取键盘输入

How can I read keyboard input in Python

我在 Python 中遇到键盘输入问题。我试过 raw_input 并且只调用了一次。但我想在每次用户按下任意键时读取键盘输入。我该怎么做?感谢您的回答。

在python2.x中,简单地使用无限while循环和条件break:

In [11]: while True:
    ...:     k = raw_input('> ')
    ...:     if k == 'q':
    ...:         break;
    ...:     #do-something


> test

> q

In [12]: 

例如,您有这样的 Python 代码:

file1.py

#!/bin/python
... do some stuff...

并且在文档的某个位置您希望始终检查输入:

while True:
    input = raw_input(">>>")
    ... do something with the input...

那将一直等待输入。您可以将该无限循环作为一个单独的进程进行线程处理,同时执行其他操作,以便用户输入可以对您正在执行的任务产生影响。

如果您只想在按下某个键时请求输入,并以循环方式执行此操作,则使用此代码(取自 this ActiveState recipe by Steven D'Aprano)您可以等待按键按下,并且然后请求输入,执行任务并 return 回到之前的状态。

import sys

try:
    import tty, termios
except ImportError:
    # Probably Windows.
    try:
        import msvcrt
    except ImportError:
        # FIXME what to do on other platforms?
        # Just give up here.
        raise ImportError('getch not available')
    else:
        getch = msvcrt.getch
else:
    def getch():
        """getch() -> key character

        Read a single keypress from stdin and return the resulting character. 
        Nothing is echoed to the console. This call will block if a keypress 
        is not already available, but will not wait for Enter to be pressed. 

        If the pressed key was a modifier key, nothing will be detected; if
        it were a special function key, it may return the first character of
        of an escape sequence, leaving additional characters in the buffer.
        """
        fd = sys.stdin.fileno()
        old_settings = termios.tcgetattr(fd)
        try:
            tty.setraw(fd)
            ch = sys.stdin.read(1)
        finally:
            termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
        return ch

那么如何处理呢?好吧,现在每次您想等待按键时只需调用 getch() 即可。就像这样:

while True:
    getch() # this also returns the key pressed, if you want to store it
    input = raw_input("Enter input")
    do_whatever_with_it

您也可以同时执行其他任务。

请记住,Python 3.x 不再使用 raw_input,而是简单地使用 input()。