对不起老问题。我已经澄清了。如何用我糟糕的线程类启动停止线程？
编辑：它在循环中，我想在代码的开头再次重新启动它。我怎样才能开始-停止-重启-停止-重启？
我的课：
import threading
class Concur(threading.Thread):
def __init__(self):
self.stopped = False
threading.Thread.__init__(self)
def run(self):
i = 0
while not self.stopped:
time.sleep(1)
i = i + 1
在主代码中，我想要：
inst = Concur()
while conditon:
inst.start()
#after some operation
inst.stop()
#some other operation
您实际上无法停止然后重新启动线程，因为在其方法终止后您无法start()再次调用其方法。run()但是，您可以通过使用threading.Condition变量来停止执行，然后在稍后恢复执行，以避免在检查或更改其运行状态时出现并发问题。
threading.Condition对象有一个关联的threading.Lock对象和方法来等待它被释放，并在发生时通知任何等待的线程。这是一个从您的问题中的代码派生的示例，它显示了这一点。在示例代码中，我将Condition变量作为Thread子类实例的一部分，以更好地封装实现并避免需要引入额外的全局变量：
from __future__ import print_function
import threading
import time
class Concur(threading.Thread):
def __init__(self):
super(Concur, self).__init__()
self.iterations = 0
self.daemon = True # Allow main to exit even if still running.
self.paused = True # Start out paused.
self.state = threading.Condition()
def run(self):
self.resume()
while True:
with self.state:
if self.paused:
self.state.wait() # Block execution until notified.
# Do stuff...
time.sleep(.1)
self.iterations += 1
def pause(self):
with self.state:
self.paused = True # Block self.
def resume(self):
with self.state:
self.paused = False
self.state.notify() # Unblock self if waiting.
class Stopwatch(object):
""" Simple class to measure elapsed times. """
def start(self):
""" Establish reference point for elapsed time measurements. """
self.start_time = time.time()
return self
@property
def elapsed_time(self):
""" Seconds since started. """
try:
return time.time() - self.start_time
except AttributeError: # Wasn't explicitly started.
self.start_time = time.time()
return 0
MAX_RUN_TIME = 5 # Seconds.
concur = Concur()
stopwatch = Stopwatch()
print('Running for {} seconds...'.format(MAX_RUN_TIME))
concur.start()
while stopwatch.elapsed_time < MAX_RUN_TIME:
concur.resume()
# Can also do other concurrent operations here...
concur.pause()
# Do some other stuff...
# Show Concur thread executed.
print('concur.iterations: {}'.format(concur.iterations))
这是大卫赫弗南的想法的充实。下面的示例运行 1 秒，然后停止 1 秒，然后运行 1 秒，依此类推。
import time
import threading
import datetime as DT
import logging
logger = logging.getLogger(__name__)
def worker(cond):
i = 0
while True:
with cond:
cond.wait()
logger.info(i)
time.sleep(0.01)
i += 1
logging.basicConfig(level=logging.DEBUG,
format='[%(asctime)s %(threadName)s] %(message)s',
datefmt='%H:%M:%S')
cond = threading.Condition()
t = threading.Thread(target=worker, args=(cond, ))
t.daemon = True
t.start()
start = DT.datetime.now()
while True:
now = DT.datetime.now()
if (now-start).total_seconds() > 60: break
if now.second % 2:
with cond:
cond.notify()