Python無阻塞控制檯輸入

Question

我想在Python中做一個簡單的IRC客戶端（當我學習語言時，作爲一種項目）。

我有一個循環，我用來接收和解析什麼IRC服務器發送給我，但如果我使用raw_input輸入的東西，它停止死循環直到我輸入的東西（顯然）。

如何在不停止循環的情況下輸入內容？

在此先感謝。

（我不認爲我需要張貼代碼，我只是想輸入的東西，而不而1循環停止。）

編輯：我在Windows上。

Answer 1

對於Windows，控制檯只，使用msvcrt模塊：

import msvcrt 

num = 0 
done = False 
while not done: 
    print(num) 
    num += 1 

    if msvcrt.kbhit(): 
     print "you pressed",msvcrt.getch(),"so now i will quit" 
     done = True 

對於Linux，這article介紹了以下解決方案，它需要termios模塊：

import sys 
import select 
import tty 
import termios 

def isData(): 
    return select.select([sys.stdin], [], [], 0) == ([sys.stdin], [], []) 

old_settings = termios.tcgetattr(sys.stdin) 
try: 
    tty.setcbreak(sys.stdin.fileno()) 

    i = 0 
    while 1: 
     print(i) 
     i += 1 

     if isData(): 
      c = sys.stdin.read(1) 
      if c == '\x1b':   # x1b is ESC 
       break 

finally: 
    termios.tcsetattr(sys.stdin, termios.TCSADRAIN, old_settings) 

對於跨平臺的，或如果你想要一個圖形用戶界面，你可以使用Pygame：

import pygame 
from pygame.locals import * 

def display(str): 
    text = font.render(str, True, (255, 255, 255), (159, 182, 205)) 
    textRect = text.get_rect() 
    textRect.centerx = screen.get_rect().centerx 
    textRect.centery = screen.get_rect().centery 

    screen.blit(text, textRect) 
    pygame.display.update() 

pygame.init() 
screen = pygame.display.set_mode((640,480)) 
pygame.display.set_caption('Python numbers') 
screen.fill((159, 182, 205)) 

font = pygame.font.Font(None, 17) 

num = 0 
done = False 
while not done: 
    display(str(num)) 
    num += 1 

    pygame.event.pump() 
    keys = pygame.key.get_pressed() 
    if keys[K_ESCAPE]: 
     done = True 

Answer 2

在Linux上，這是對mizipzor代碼的重構，使得它更容易一些，以防萬一您必須在多個地方使用此代碼。

import sys 
import select 
import tty 
import termios 

class NonBlockingConsole(object): 

    def __enter__(self): 
     self.old_settings = termios.tcgetattr(sys.stdin) 
     tty.setcbreak(sys.stdin.fileno()) 
     return self 

    def __exit__(self, type, value, traceback): 
     termios.tcsetattr(sys.stdin, termios.TCSADRAIN, self.old_settings) 


    def get_data(self): 
     if select.select([sys.stdin], [], [], 0) == ([sys.stdin], [], []): 
      return sys.stdin.read(1) 
     return False 

以下是如何使用此代碼：此代碼將打印一個計數器，該計數器會持續增長，直到您按ESC。

with NonBlockingConsole() as nbc: 
    i = 0 
    while 1: 
     print i 
     i += 1 
     if nbc.get_data() == '\x1b': # x1b is ESC 
      break 

Answer 3

這裏，使用一個單獨的線程在Linux和Windows上運行的解決方案：

import sys 
import threading 
import time 
import Queue 

def add_input(input_queue): 
    while True: 
     input_queue.put(sys.stdin.read(1)) 

def foobar(): 
    input_queue = Queue.Queue() 

    input_thread = threading.Thread(target=add_input, args=(input_queue,)) 
    input_thread.daemon = True 
    input_thread.start() 

    last_update = time.time() 
    while True: 

     if time.time()-last_update>0.5: 
      sys.stdout.write(".") 
      last_update = time.time() 

     if not input_queue.empty(): 
      print "\ninput:", input_queue.get() 

foobar() 

Answer 4

這是最真棒solution 我見過。如果鏈接粘貼在這裏下山：

#!/usr/bin/env python 
''' 
A Python class implementing KBHIT, the standard keyboard-interrupt poller. 
Works transparently on Windows and Posix (Linux, Mac OS X). Doesn't work 
with IDLE. 

This program is free software: you can redistribute it and/or modify 
it under the terms of the GNU Lesser General Public License as 
published by the Free Software Foundation, either version 3 of the 
License, or (at your option) any later version. 

This program is distributed in the hope that it will be useful, 
but WITHOUT ANY WARRANTY; without even the implied warranty of 
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 
GNU General Public License for more details. 

''' 

import os 

# Windows 
if os.name == 'nt': 
    import msvcrt 

# Posix (Linux, OS X) 
else: 
    import sys 
    import termios 
    import atexit 
    from select import select 


class KBHit: 

    def __init__(self): 
     '''Creates a KBHit object that you can call to do various keyboard things. 
     ''' 

     if os.name == 'nt': 
      pass 

     else: 

      # Save the terminal settings 
      self.fd = sys.stdin.fileno() 
      self.new_term = termios.tcgetattr(self.fd) 
      self.old_term = termios.tcgetattr(self.fd) 

      # New terminal setting unbuffered 
      self.new_term[3] = (self.new_term[3] & ~termios.ICANON & ~termios.ECHO) 
      termios.tcsetattr(self.fd, termios.TCSAFLUSH, self.new_term) 

      # Support normal-terminal reset at exit 
      atexit.register(self.set_normal_term) 


    def set_normal_term(self): 
     ''' Resets to normal terminal. On Windows this is a no-op. 
     ''' 

     if os.name == 'nt': 
      pass 

     else: 
      termios.tcsetattr(self.fd, termios.TCSAFLUSH, self.old_term) 


    def getch(self): 
     ''' Returns a keyboard character after kbhit() has been called. 
      Should not be called in the same program as getarrow(). 
     ''' 

     s = '' 

     if os.name == 'nt': 
      return msvcrt.getch().decode('utf-8') 

     else: 
      return sys.stdin.read(1) 


    def getarrow(self): 
     ''' Returns an arrow-key code after kbhit() has been called. Codes are 
     0 : up 
     1 : right 
     2 : down 
     3 : left 
     Should not be called in the same program as getch(). 
     ''' 

     if os.name == 'nt': 
      msvcrt.getch() # skip 0xE0 
      c = msvcrt.getch() 
      vals = [72, 77, 80, 75] 

     else: 
      c = sys.stdin.read(3)[2] 
      vals = [65, 67, 66, 68] 

     return vals.index(ord(c.decode('utf-8'))) 


    def kbhit(self): 
     ''' Returns True if keyboard character was hit, False otherwise. 
     ''' 
     if os.name == 'nt': 
      return msvcrt.kbhit() 

     else: 
      dr,dw,de = select([sys.stdin], [], [], 0) 
      return dr != [] 


# Test  
if __name__ == "__main__": 

    kb = KBHit() 

    print('Hit any key, or ESC to exit') 

    while True: 

     if kb.kbhit(): 
      c = kb.getch() 
      if ord(c) == 27: # ESC 
       break 
      print(c) 

    kb.set_normal_term() 

_{通過Simon D. Levy製成，一個compilation of software的一部分，他撰寫並下Gnu Lesser General Public License釋放。}

Answer 5

使用python3.3及以上版本，您可以使用asyncio模塊，如本答案中所述。 您必須重新考慮代碼才能使用asyncio。 Prompt for user input using python asyncio.create_server instance

Answer 6

我覺得curses庫可以提供幫助。

import curses 
import datetime 

stdscr = curses.initscr() 
curses.noecho() 
stdscr.nodelay(1) # set getch() non-blocking 

stdscr.addstr(0,0,"Press \"p\" to show count, \"q\" to exit...") 
line = 1 
try: 
    while 1: 
     c = stdscr.getch() 
     if c == ord('p'): 
      stdscr.addstr(line,0,"Some text here") 
      line += 1 
     elif c == ord('q'): break 

     """ 
     Do more things 
     """ 

finally: 
    curses.endwin()