是否有办法从用户输入中读取单个字符?例如,他们在终端上按下一个键,它就会返回(有点像getch())。我知道Windows中有这个功能,但我想要跨平台的东西。


当前回答

另一种方法:

import os
import sys    
import termios
import fcntl

def getch():
  fd = sys.stdin.fileno()

  oldterm = termios.tcgetattr(fd)
  newattr = termios.tcgetattr(fd)
  newattr[3] = newattr[3] & ~termios.ICANON & ~termios.ECHO
  termios.tcsetattr(fd, termios.TCSANOW, newattr)

  oldflags = fcntl.fcntl(fd, fcntl.F_GETFL)
  fcntl.fcntl(fd, fcntl.F_SETFL, oldflags | os.O_NONBLOCK)

  try:        
    while 1:            
      try:
        c = sys.stdin.read(1)
        break
      except IOError: pass
  finally:
    termios.tcsetattr(fd, termios.TCSAFLUSH, oldterm)
    fcntl.fcntl(fd, fcntl.F_SETFL, oldflags)
  return c

摘自这篇博文。

其他回答

我对python3的解决方案,不依赖于任何pip包。

# precondition: import tty, sys
def query_yes_no(question, default=True):
    """
    Ask the user a yes/no question.
    Returns immediately upon reading one-char answer.
    Accepts multiple language characters for yes/no.
    """
    if not sys.stdin.isatty():
        return default
    if default:
        prompt = "[Y/n]?"
        other_answers = "n"
    else:
        prompt = "[y/N]?"
        other_answers = "yjosiá"

    print(question,prompt,flush= True,end=" ")
    oldttysettings = tty.tcgetattr(sys.stdin.fileno())
    try:
        tty.setraw(sys.stdin.fileno())
        return not sys.stdin.read(1).lower() in other_answers
    except:
        return default
    finally:
        tty.tcsetattr(sys.stdin.fileno(), tty.TCSADRAIN , oldttysettings)
        sys.stdout.write("\r\n")
        tty.tcdrain(sys.stdin.fileno())

如果你只是想按住屏幕,这样你就可以在终端上看到结果

input()

在代码的末尾,它将保存屏幕

python中的curses包可以使用一些语句从终端进入“原始”模式进行字符输入。Curses的主要用途是接管屏幕进行输出,这可能不是你想要的。此代码片段使用print()语句代替,这是可用的,但必须注意curses如何更改附加到输出的行结束符。

#!/usr/bin/python3
# Demo of single char terminal input in raw mode with the curses package.
import sys, curses

def run_one_char(dummy):
    'Run until a carriage return is entered'
    char = ' '
    print('Welcome to curses', flush=True)
    while ord(char) != 13:
        char = one_char()

def one_char():
    'Read one character from the keyboard'
    print('\r? ', flush= True, end = '')

    ## A blocking single char read in raw mode. 
    char = sys.stdin.read(1)
    print('You entered %s\r' % char)
    return char

## Must init curses before calling any functions
curses.initscr()
## To make sure the terminal returns to its initial settings,
## and to set raw mode and guarantee cleanup on exit. 
curses.wrapper(run_one_char)
print('Curses be gone!')

这里回答:python中的raw_input,不按enter

使用这个代码-

from tkinter import Tk, Frame


def __set_key(e, root):
    """
    e - event with attribute 'char', the released key
    """
    global key_pressed
    if e.char:
        key_pressed = e.char
        root.destroy()


def get_key(msg="Press any key ...", time_to_sleep=3):
    """
    msg - set to empty string if you don't want to print anything
    time_to_sleep - default 3 seconds
    """
    global key_pressed
    if msg:
        print(msg)
    key_pressed = None
    root = Tk()
    root.overrideredirect(True)
    frame = Frame(root, width=0, height=0)
    frame.bind("<KeyRelease>", lambda f: __set_key(f, root))
    frame.pack()
    root.focus_set()
    frame.focus_set()
    frame.focus_force()  # doesn't work in a while loop without it
    root.after(time_to_sleep * 1000, func=root.destroy)
    root.mainloop()
    root = None  # just in case
    return key_pressed


def __main():
        c = None
        while not c:
                c = get_key("Choose your weapon ... ", 2)
        print(c)

if __name__ == "__main__":
    __main()

参考:https://github.com/unfor19/mg-tools/blob/master/mgtools/get_key_pressed.py

两个答案中逐字引用的ActiveState配方是过度设计的。它可以归结为:

def _find_getch():
    try:
        import termios
    except ImportError:
        # Non-POSIX. Return msvcrt's (Windows') getch.
        import msvcrt
        return msvcrt.getch

    # POSIX system. Create and return a getch that manipulates the tty.
    import sys, tty
    def _getch():
        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

    return _getch

getch = _find_getch()