如何在Python中的线程循环中引发异常?

用户名

我正在寻找一种在True True循环中引发异常的方法。引发异常的信号起源于线程t_run,该线程连续检查称为pingresponse的全局布尔变量。只要pingresponse等于“ False”,就应该立即中断while True循环。我不希望在while True循环中连续检查变量pingresponse,以检查是否必须引发异常。

到目前为止,我的草稿如下:

import time
import threading
import random

def run():
    # this thread continuously checks the pingresponse
    global pingresponse

    while True:
        # simulating a random pingresponse
        if random.random() > 0.8:
            pingresponse = False
        else:
            pingresponse = True
        time.sleep(0.001)

pingresponse = True
t_run = threading.Thread(target=run)
t_run.start()

while True:
    i = 0
    while True:
        try:
            print('While True loop iteration', i)
            print('pingresponse:' ,pingresponse)
            i += 1

            # "do some work" which includes several consecutive and encapsulated while and for loops
            time.sleep(1) # simulate "do some work" and prevent infinite looping if executed

            # What I want is immediately interrupting the inner while True loop by raising an exception
            # as soon as pingresponse was set to False in the t_run thread
            # The exception should be raised independently of the current position in "do some work"

            # What I don't want is to check the pingresponse variable all the time in "do some work":
            # if not pingresponse:
            #   raise Exception

        except Exception:
            print('pingresponse was set to False in the t_run thread')
            print('start while True loop again with iteration 0')
            break
第二次世界大战

这个答案使用方法How to exit the entire application from a Python thread?修改您的示例以在发生异常时停止所有操作_thread.interrupt_main()在主线程中引发键盘中断。

import time
import threading
import _thread
import random

def run():
    # this thread continously checks the pingresponse
    global pingresponse

    while True:
        # simulating a random pingresponse
        x = random.random()
        print(f'x:{x:1.3f}')
        if x > 0.98:
            pingresponse = False
        else:
            pingresponse = True
        time.sleep(0.001)
        if not pingresponse:
            _thread.interrupt_main()
            break

pingresponse = True
t_run = threading.Thread(target=run)
t_run.start()

foo = True
while foo:
    i = 0
    while True:
        try:
            print('While True loop iteration', i)
            print('pingresponse:' ,pingresponse)
            i += 1

            # "do some work" which includes several consecutive and encapsulated while and for loops
            time.sleep(1) # simulate "do some work" and prevent infinite looping if executed

        except KeyboardInterrupt as e:
            print('pingresponse was set to False in the t_run thread')
            print('start while True loop again with iteration 0')
            # print(e)
            foo = False
            # raise
            break
    if foo: break

如果使用_thread.interrupt_main(),可能需要考虑一些事情-您应该花一些时间进行研究。可能希望在该过程中包括信号模块
如何在Python中捕获SIGINT?看起来值得。

本文收集自互联网,转载请注明来源。

如有侵权,请联系 [email protected] 删除。

编辑于
0

我来说两句

0 条评论
登录 后参与评论

相关文章