多线程的学习笔记

多线程 的创建、启动、停止

import ctypes
import inspect
import threading
import time

def main(a):
while True:
time.sleep(1)
print(a)

class myThread(threading.Thread): # 继承父类 threading.Thread
def init(self, name):
threading.Thread.init(self)
self.name = name

def run(self):  # 把要执行的代码写到run函数里面 线程在创建后会直接运行run函数
    main(self.name)
    print('执行线程了')
    print(self.name)

def _async_raise(tid, exctype):
“““raises the exception, performs cleanup if needed”””
tid = ctypes.c_long(tid)
if not inspect.isclass(exctype):
exctype = type(exctype)
res = ctypes.pythonapi.PyThreadState_SetAsyncExc(tid, ctypes.py_object(exctype))
if res == 0:
raise ValueError(“invalid thread id”)
elif res != 1:
# “““if it returns a number greater than one, you’re in trouble,
# and you should call it again with exc=NULL to revert the effect”””
ctypes.pythonapi.PyThreadState_SetAsyncExc(tid, None)
raise SystemError(“PyThreadState_SetAsyncExc failed”)

def stop_thread(thread):
_async_raise(thread.ident, SystemExit)

if name == ‘main’:
nameList = [1, 2, 3, 4, 5, 6]
threadList = []
for name in nameList:
threadList.append(myThread(str(name)))

# 开启线程
for thread in threadList:
    thread.start()

# 停止线程
time.sleep(1)
for thread in threadList:
    print(threadList.index(thread))
    stop_thread(thread)
    print('stop%s'%thread)

在一些网页打开的过程中，当可能出现 a\b\c\d 4 种不同情况且当出现一种，其他情况就不出现的情景，这时候可以选择多线程，实时监控哪个情况出现，当出现处理该情况的逻辑，其余就停止掉