我正在使用Python 3编写一个程序，需要在一定时间内询问用户多个输入。以下是我的尝试：
from threading import Timer
##
def timeup():
global your_time
your_time = False
return your_time
##
timeout = 5
your_Time = True
t = Timer(timeout, timeup)
t.start()
##
while your_time == True:
input()
t.cancel()
print('Stop typing!')
问题在于，即使时间到了，代码仍在等待输入。我希望循环在时间完全用尽时停止。我该怎么做？谢谢！
这个解决方案是跨平台的，立即中断打字操作以通知已存在的超时。它不必等到用户按下ENTER键才发现超时发生了。除了及时通知用户外，这还确保了超时后没有输入会被进一步处理。
特性
这个答案使用了一个线程管理器实例，它在一个单独的提示线程和主线程之间进行调解。管理线程检查超时并把来自提示线程的输入转发给父线程。这种设计使得在需要使MainThread非阻塞的情况下容易进行修改（在_poll中更改以取代阻塞的queue.get()）。
在超时时，管理线程请求按下ENTER键继续，并使用 threading.Event 实例来确保在继续之前提示线程关闭。有关特定方法的详细信息，请参见文档文本：
from threading import Thread, Event
from queue import Queue, Empty
import time
SENTINEL = object()
class PromptManager(Thread):
def __init__(self, timeout):
super().__init__()
self.timeout = timeout
self._in_queue = Queue()
self._out_queue = Queue()
self.prompter = Thread(target=self._prompter, daemon=True)
self.start_time = None
self._prompter_exit = Event() # synchronization for shutdown
self._echoed = Event() # synchronization for terminal output
def run(self):
"""Run in worker-thread. Start prompt-thread, fetch passed
inputs from in_queue and check for timeout. Forward inputs for
`_poll` in parent. If timeout occurs, enqueue SENTINEL to
break the for-loop in `_poll()`.
"""
self.start_time = time.time()
self.prompter.start()
while self.time_left > 0:
try:
txt = self._in_queue.get(timeout=self.time_left)
except Empty:
self._out_queue.put(SENTINEL)
else:
self._out_queue.put(txt)
print("\nTime is out! Press ENTER to continue.")
self._prompter_exit.wait()
@property
def time_left(self):
return self.timeout - (time.time() - self.start_time)
def start(self):
"""Start manager-thread."""
super().start()
self._poll()
def _prompter(self):
"""Prompting target function for execution in prompter-thread."""
while self.time_left > 0:
self._in_queue.put(input('>$ '))
self._echoed.wait() # prevent intermixed display
self._echoed.clear()
self._prompter_exit.set()
def _poll(self):
"""Get forwarded inputs from the manager-thread executing `run()`
and process them in the parent-thread.
"""
for msg in iter(self._out_queue.get, SENTINEL):
print(f'you typed: {msg}')
self._echoed.set()
# finalize
self._echoed.set()
self._prompter_exit.wait()
self.join()
if __name__ == '__main__':
pm = PromptManager(timeout=5)
pm.start()
示例输出:
>$ Hello
you typed: Hello
>$ Wor
Time is out! Press ENTER to continue.
Process finished with exit code 0
import select,sys
def timed_input(sec):
po= select.poll() # creating a poll object
# register the standard input for polling with the file number
po.register(sys.stdin.fileno(), select.POLLIN)
while True:
# start the poll
events= po.poll(sec*1000) # timeout: milliseconds
if not events:
print("\n Sorry, it's too late...")
return ""
for fno,ev in events: # check the events and the corresponding fno
if fno == sys.stdin.fileno(): # in our case this is the only one
return(input())
s=timed_input(10)
print("From keyboard:",s)
标准输入(stdin)会缓存按下的键，而input()函数会一次性读取该缓存。
from datetime import datetime, timedelta
t = 5 # You can type for 5 seconds
def timeup():
final_time = datetime.now() + timedelta(seconds=t)
print("You can enter now for" + str(t) + " seconds")
while datetime.now() < final_time:
input()
print("STOP TYPING")
timeup()
import timeimport threading timer = 5 timeout = time.time() + 1 * timer def do_input(): while True: message = input("Message: ") def do_timer(): while time.time() < timeout: continue print("\n计时器已结束！") exit() for i in range(1): thread = threading.Thread(target=do_input) thread.daemon = True thread.start() thread1 = threading.Thread(target=do_timer).start() - Feitan Portortime.sleep以防止占用 CPU），而exit()在终端中可以工作，但在 IDE 控制台中无法工作（改为sys.exit()）。 - Darkonaut