Python，停止线程

Question

我正在尝试创建一个 ping IP 地址并记录连接/未连接时间的类。

由于这个类是 GUI 的一部分，我希望在用户询问时停止这个线程。

发现一些 Q&A 重新评估了这个问题，但没有一个真正导致线程停止。

我正在尝试创建一个方法，该类的一部分将停止self.run()

这是我的Pinger 课程：

class Pinger(threading.Thread):
    def __init__(self, address='', rate=1):
        threading.Thread.__init__(self)

        self.address = address
        self.ping_rate = rate
        self.ping_vector, self.last_ping = [], -1
        self.start_time, self.last_status = datetime.datetime.now(), []
        self.timestamp, self.time_vector = 0, [datetime.timedelta(0)] * 4

    def run(self):
            self.start_ping()

    def start_ping(self):
        self.timestamp = datetime.datetime.now()
        while True:
            ping_result = os.system('ping %s -n 1 >Null' % self.address)
            self.ping_vector.append(ping_result)

            if self.last_ping != ping_result:
                text = ['Reachable', 'Lost']
                print(str(self.timestamp)[:-4], self.address, text[ping_result])

            round_time_qouta = datetime.datetime.now() - self.timestamp
            self.timestamp = datetime.datetime.now()
            self.update_time_counter(ping_result, round_time_qouta)

            self.last_ping = ping_result
            time.sleep(self.ping_rate)

    def update_time_counter(self, ping_result=0, time_quota=datetime.timedelta(0)):
        """self.time_vector = [[cons.succ ping time],[cons.not_succ ping time],
        [max accum succ ping time],[max accum not_succ ping time] """

        p_vec = [0, 1]

        self.time_vector[p_vec[ping_result]] += time_quota
        if self.time_vector[p_vec[ping_result]].total_seconds() > self.time_vector[
            p_vec[ping_result] + 2].total_seconds():
            self.time_vector[p_vec[ping_result] + 2] = self.time_vector[p_vec[ping_result]]

        self.time_vector[p_vec[ping_result - 1]] = datetime.timedelta(0)

        self.last_status = [ping_result, self.chop_milisecond(self.time_vector[ping_result]),
                            self.chop_milisecond(self.time_vector[ping_result + 2]),
                            self.chop_milisecond(datetime.datetime.now() - self.start_time)]

        print(str(self.timestamp)[:-4], "State: " + ['Received', 'Lost'][ping_result],
              " Duration: " + self.last_status[1], " Max Duration: " + self.last_status[2],
              "Total time: " + self.last_status[3])

    def chop_milisecond(self, time):
        return str(time).split('.')[0]

Answer 1

正如我在评论中所说，最简单的方法是使用threading.Event 在线程应该退出时发出信号。这样您就可以公开该事件并让其他线程设置它，同时您可以从您的线程中检查其状态并根据请求退出。

在你的情况下，它可能很简单：

class Pinger(threading.Thread):

    def __init__(self, address='', rate=1):
        threading.Thread.__init__(self)
        self.kill = threading.Event()
        # the rest of your setup...

    # etc.

    def start_ping(self):
        self.timestamp = datetime.datetime.now()
        while not self.kill.is_set():
            # do your pinging stuff

    # etc.

然后，当您希望线程停止时（例如从您的 UI 中），只需调用它：pinger_instance.kill.set()，您就完成了。请记住，由于阻塞 os.system() 调用以及您在 Pinger.start_ping() 方法末尾的 time.sleep()，它需要一些时间才能被杀死。

Answer 2

感谢@zwer 的领导。 这是我的完整代码（已标记更改）

class Pinger(threading.Thread):
    def __init__(self, address='', rate=1):
        threading.Thread.__init__(self)

        self.address = address
        self.ping_rate = rate
        self.ping_vector, self.last_ping = [], -1
        self.start_time, self.last_status = datetime.datetime.now(), []
        self.timestamp, self.time_vector = 0, [datetime.timedelta(0)] * 4
        self.event = threading.Event() # <---- Added

    def run(self):
        while not self.event.is_set(): # <---- Added
            self.start_ping()
            self.event.wait(self.ping_rate) # <---- Added ( Time to repeat moved in here )

    def stop(self):       # <---- Added ( ease of use )
        self.event.set()  # <---- Added ( set to False and causes to stop )


    def start_ping(self):
        self.timestamp = datetime.datetime.now()
        # While loop ##--- > Deleted. now it loops in run method #####
        ping_result = os.system('ping %s -n 1 >Null' % self.address)
        self.ping_vector.append(ping_result)

        if self.last_ping != ping_result:
            text = ['Reachable', 'Lost']
            print(str(self.timestamp)[:-4], self.address, text[ping_result])

        round_time_qouta = datetime.datetime.now() - self.timestamp
        self.timestamp = datetime.datetime.now()
        self.update_time_counter(ping_result, round_time_qouta)

        self.last_ping = ping_result
        #### time.sleep (self.ping_rate)  # <---- deleted 

    def update_time_counter(self, ping_result=0, time_quota=datetime.timedelta(0)):
        """self.time_vector = [[cons.succ ping time],[cons.not_succ ping time],
        [max accum succ ping time],[max accum not_succ ping time] """

        p_vec = [0, 1]

        self.time_vector[p_vec[ping_result]] += time_quota
        if self.time_vector[p_vec[ping_result]].total_seconds() > self.time_vector[
            p_vec[ping_result] + 2].total_seconds():
            self.time_vector[p_vec[ping_result] + 2] = self.time_vector[p_vec[ping_result]]

        self.time_vector[p_vec[ping_result - 1]] = datetime.timedelta(0)

        self.last_status = [ping_result, self.chop_milisecond(self.time_vector[ping_result]),
                            self.chop_milisecond(self.time_vector[ping_result + 2]),
                            self.chop_milisecond(datetime.datetime.now() - self.start_time)]

        print(str(self.timestamp)[:-4], "State: " + ['Received', 'Lost'][ping_result],
              " Duration: " + self.last_status[1], " Max Duration: " + self.last_status[2],
              "Total time: " + self.last_status[3])

    def chop_milisecond(self, time):
        return str(time).split('.')[0]

    def get_status(self):
        return self.last_status


c = Pinger('127.0.0.1', 5)
c.start()
time.sleep(10)
c.stop()

Answer 3

使用_Thread_stop()：

MyPinger._Thread__stop()

Answer 4

我会对你的类进行一些不同的编码，以作为守护进程运行。

保留 start_ping 代码并使用下一个代码：

MyPinger = threading.Thread(target = self.start_ping, name="Pinger")
MyPinger.setDaemon(True)
MyPinger.start() # launch start_ping

并且可以使用 _Thread_stop() 来阻止它，这有点野蛮......：

if MyPinger.IsAlive():
   MyPinger._Thread__stop()