Question

我正在寻找一种方法，当用户按下[空格键]时暂停下面的for循环，然后再次按下[空格键]时从最近的迭代继续循环。

目前，脚本会提示用户输入三个值，然后按时间间隔打印文本文件中的单词，直到没有剩余单词为止。

最好的方法是什么？非常感谢。

import time

with open('Textfile.txt', 'r', encoding='utf8') as file:

    data = file.read()
    data2 = data.split()


def reading(start, speed, chunks):

    for i in range(start, len(data2), chunks):

        print('\r' + (' '.join(data2[i:i+chunks])), end="")

        time.sleep(60 / speed * chunks)

    print ("The End.")


start = int(input('Where would you like to start? (word number) '))
speed = int(input('How many words per minute? '))
chunks = int(input('How many words at a time? '))

reading(start, speed, chunks)

Answer 1

这是你问题的部分答案（关于空间的部分没有回答，但是请读到最后，有一些提示）。我从这里改编了答案Non-blocking read on a subprocess.PIPE in python。

import time
import sys
from threading import Thread
try:
    from Queue import Queue, Empty
except ImportError:
    from queue import Queue, Empty  # python 3.x


def enqueue_output(output, queue):
    for line in iter(output, b''):
        queue.put(line)
    out.close()


with open('Textfile.txt', 'r', encoding='utf8') as file:
    data = file.read()
    data2 = data.split()


def reading(start, speed, chunks):
    q = Queue()
    t = Thread(target=enqueue_output, args=(sys.stdin.readline, q))
    t.daemon = True # thread dies with the program
    t.start()

    for i in range(start, len(data2), chunks):
        print('\r' + (' '.join(data2[i:i+chunks])), end="")
        time.sleep(60 / speed * chunks)

        try:
            line = q.get_nowait() # or q.get(timeout=.1)
        except Empty:
            pass
        else:
            print("Pausing")
            while 1:
                time.sleep(0.3) # Adjust frequency of reading user's input
                try:
                    line = q.get_nowait() # or q.get(timeout=.1)
                except Empty:
                    pass
                else:
                    print("Resuming")
                    break

    print ("The End.")


start = int(input('Where would you like to start? (word number) '))
speed = int(input('How many words per minute? '))
chunks = int(input('How many words at a time? '))

reading(start, speed, chunks)

使用此用户可以按Enter按钮暂停/恢复阅读。对于空间，您可以尝试使用此答案How to get user input during a while loop without blocking

中的食谱

...或使用一些控制台ui（curses，urwid，...）或gui（tkinter，pyqt，...）模块。

Python - 使用[spacebar]暂停循环

1 个答案: