相当于setInterval（）的Python吗？

Question

Python是否具有类似于JavaScript的功能setInterval()？谢谢

Answer 1

这可能是您正在寻找的正确片段：

import threading

def set_interval(func, sec):

    def func_wrapper():

        set_interval(func, sec)

        func()

    t = threading.Timer(sec, func_wrapper)

    t.start()

    return t

Answer 2

这是您可以启动和停止的版本。它没有阻塞。由于没有添加执行时间错误，因此也没有毛刺（例如，对于音频间隔很短的长时间执行很重要）

import time, threading

StartTime=time.time()

def action() :

    print('action ! -> time : {:.1f}s'.format(time.time()-StartTime))

class setInterval :

    def __init__(self,interval,action) :

        self.interval=interval

        self.action=action

        self.stopEvent=threading.Event()

        thread=threading.Thread(target=self.__setInterval)

        thread.start()

    def __setInterval(self) :

        nextTime=time.time()+self.interval

        while not self.stopEvent.wait(nextTime-time.time()) :

            nextTime+=self.interval

            self.action()

    def cancel(self) :

        self.stopEvent.set()

# start action every 0.6s

inter=setInterval(0.6,action)

print('just after setInterval -> time : {:.1f}s'.format(time.time()-StartTime))

# will stop interval in 5s

t=threading.Timer(5,inter.cancel)

t.start()

输出为：

just after setInterval -> time : 0.0s

action ! -> time : 0.6s

action ! -> time : 1.2s

action ! -> time : 1.8s

action ! -> time : 2.4s

action ! -> time : 3.0s

action ! -> time : 3.6s

action ! -> time : 4.2s

action ! -> time : 4.8s

Answer 3

只要保持它的美观和简单即可。

import threading

def setInterval(func,time):

    e = threading.Event()

    while not e.wait(time):

        func()

def foo():

    print "hello"

# using

setInterval(foo,5)

# output:

hello

hello

.

.

.

编辑：此代码是非阻塞的

import threading

class ThreadJob(threading.Thread):

    def __init__(self,callback,event,interval):

        '''runs the callback function after interval seconds

        :param callback:  callback function to invoke

        :param event: external event for controlling the update operation

        :param interval: time in seconds after which are required to fire the callback

        :type callback: function

        :type interval: int

        '''

        self.callback = callback

        self.event = event

        self.interval = interval

        super(ThreadJob,self).__init__()

    def run(self):

        while not self.event.wait(self.interval):

            self.callback()

event = threading.Event()

def foo():

    print "hello"

k = ThreadJob(foo,event,2)

k.start()

print "It is non-blocking"