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Python實(shí)現(xiàn)多線程的兩種方式分析

更新時(shí)間：2018年08月29日 09:15:15 作者：xiaofei0859

這篇文章主要介紹了Python實(shí)現(xiàn)多線程的兩種方式,結(jié)合實(shí)例形式分析了通過自定義函數(shù)傳遞Thread對(duì)象以及繼承Thread類兩種多線程實(shí)現(xiàn)方式相關(guān)操作技巧,需要的朋友可以參考下

本文實(shí)例講述了Python實(shí)現(xiàn)多線程的兩種方式。分享給大家供大家參考，具體如下：

目前python 提供了幾種多線程實(shí)現(xiàn)方式 thread，threading，multithreading ,其中thread模塊比較底層，而threading模塊是對(duì)thread做了一些包裝，可以更加方便的被使用。

2.7版本之前python對(duì)線程的支持還不夠完善，不能利用多核CPU，但是2.7版本的python中已經(jīng)考慮改進(jìn)這點(diǎn)，出現(xiàn)了multithreading 模塊。threading模塊里面主要是對(duì)一些線程的操作對(duì)象化，創(chuàng)建Thread的class。一般來說，使用線程有兩種模式:

A 創(chuàng)建線程要執(zhí)行的函數(shù)，把這個(gè)函數(shù)傳遞進(jìn)Thread對(duì)象里，讓它來執(zhí)行；
B 繼承Thread類，創(chuàng)建一個(gè)新的class，將要執(zhí)行的代碼寫到run函數(shù)里面。

本文介紹兩種實(shí)現(xiàn)方法。

第一種創(chuàng)建函數(shù)并且傳入Thread 對(duì)象中

t.py 腳本內(nèi)容

import threading,time
from time import sleep, ctime
def now() :
 return str( time.strftime( '%Y-%m-%d %H:%M:%S' , time.localtime() ) )
def test(nloop, nsec):
 print 'start loop', nloop, 'at:', now()
 sleep(nsec)
 print 'loop', nloop, 'done at:', now()
def main():
 print 'starting at:',now()
 threadpool=[]
 for i in xrange(10):
  th = threading.Thread(target= test,args= (i,2))
  threadpool.append(th)
 for th in threadpool:
  th.start()
 for th in threadpool :
  threading.Thread.join( th )
 print 'all Done at:', now()
if __name__ == '__main__':
  main()

執(zhí)行結(jié)果：

starting at: 2018-08-29 09:34:16
start loop 0 at: 2018-08-29 09:34:16
start loop 1 at: 2018-08-29 09:34:16
start loop 2 at: 2018-08-29 09:34:16start loop 3 at: 2018-08-29 09:34:16

start loop 4 start loopat: 52018-08-29 09:34:16
at: 2018-08-29 09:34:16
start loop 6 at: start loop2018-08-29 09:34:16
7 at: 2018-08-29 09:34:16
start loop 8 start loopat: 9 2018-08-29 09:34:16at:
2018-08-29 09:34:16
looploop 1 done at: 2018-08-29 09:34:18
0 done at: 2018-08-29 09:34:18
loop 3 done at: 2018-08-29 09:34:18
looploop 5 done at: 2018-08-29 09:34:18
2 done at: 2018-08-29 09:34:18
loop 4 done at: 2018-08-29 09:34:18
looploop 7 done at: 2018-08-29 09:34:18
6 done at: 2018-08-29 09:34:18
looploop 98 done at:done at: 2018-08-29 09:34:182018-08-29 09:34:18

all Done at: 2018-08-29 09:34:18

第二種創(chuàng)建繼承自Thread的類

thclass.py 腳本內(nèi)容：

import threading , time
from time import sleep, ctime
def now() :
 return str(time.strftime('%Y-%m-%d %H:%M:%S' , time.localtime()))
class myThread (threading.Thread) :
 """docstring for myThread"""
 def __init__(self, nloop, nsec) :
  super(myThread, self).__init__()
  self.nloop = nloop
  self.nsec = nsec
 def run(self):
  print 'start loop', self.nloop, 'at:', ctime()
  sleep(self.nsec)
  print 'loop', self.nloop, 'done at:', ctime()
def main():
 thpool = []
 print 'starting at:', now()
 for i in xrange(10):
  thpool.append(myThread(i, 2))
 for th in thpool:
  th.start()
 for th in thpool:
  th.join()
 print 'all Done at:', now()
if __name__ == '__main__':
  main()

執(zhí)行結(jié)果：

starting at: 2018-08-29 09:36:02
start loop 0 at: Wed Aug 29 09:36:02 2018
start loop 1 at: Wed Aug 29 09:36:02 2018
start loop 2 at: Wed Aug 29 09:36:02 2018
start loop 3 at: Wed Aug 29 09:36:02 2018
start loop 4 at: Wed Aug 29 09:36:02 2018
start loop 5 at: Wed Aug 29 09:36:02 2018
start loop 6 at: Wed Aug 29 09:36:02 2018
start loop 7 at: Wed Aug 29 09:36:02 2018
start loop 8 at: Wed Aug 29 09:36:02 2018
start loop 9 at: Wed Aug 29 09:36:02 2018
loop 0 done at: Wed Aug 29 09:36:04 2018
loop 1 done at: Wed Aug 29 09:36:04 2018
looploop 23 done at:done at: Wed Aug 29 09:36:04 2018Wed Aug 29 09:36:04 2018

loop 4 done at: Wed Aug 29 09:36:04 2018
loop 5 done at: Wed Aug 29 09:36:04 2018
loop 6 done at: Wed Aug 29 09:36:04 2018
looploop loop 8 9 7 done at: done at: done at: Wed Aug 29 09:36:04 2018 Wed Aug 29 09:36:04 2018
Wed Aug 29 09:36:04 2018

all Done at: 2018-08-29 09:36:04