Python：多线程

我们先来看看【非多线程】的例子，代码如下：

from time import ctime, sleep

def music():
    for i in range(3):
        print("【%s】Listening to music ..." % ctime())
        sleep(1)

def read():
    for i in range(3):
        print("【%s】Reading on book ..." % ctime())
        sleep(1)

if __name__ == "__main__":

    # 没有多线程处理的情况下，代码是顺序执行的，前一个没有执行完是不会执行下一个的

    music()
    read()
    print("------------------------")
    print("【%s】all over." % ctime())

from time import ctime, sleep

def music():

for i in range(3):

print("【%s】Listening to music ..." % ctime())

sleep(1)

def read():

for i in range(3):

print("【%s】Reading on book ..." % ctime())

sleep(1)

if __name__ == "__main__":

# 没有多线程处理的情况下，代码是顺序执行的，前一个没有执行完是不会执行下一个的

music()

read()

print("------------------------")

print("【%s】all over." % ctime())

它的执行结果如下：

D:\adamhuan_data\pycharm_data\python_Multi_Threads\venv\Scripts\python.exe D:/adamhuan_data/pycharm_data/python_Multi_Threads/multi_threads.py
【Sat Oct  9 11:11:47 2021】Listening to music ...
【Sat Oct  9 11:11:48 2021】Listening to music ...
【Sat Oct  9 11:11:49 2021】Listening to music ...
【Sat Oct  9 11:11:50 2021】Reading on book ...
【Sat Oct  9 11:11:51 2021】Reading on book ...
【Sat Oct  9 11:11:52 2021】Reading on book ...
------------------------
【Sat Oct  9 11:11:53 2021】all over.

Process finished with exit code 0

D:\adamhuan_data\pycharm_data\python_Multi_Threads\venv\Scripts\python.exe D:/adamhuan_data/pycharm_data/python_Multi_Threads/multi_threads.py

【Sat Oct 9 11:11:47 2021】Listening to music ...

【Sat Oct 9 11:11:48 2021】Listening to music ...

【Sat Oct 9 11:11:49 2021】Listening to music ...

【Sat Oct 9 11:11:50 2021】Reading on book ...

【Sat Oct 9 11:11:51 2021】Reading on book ...

【Sat Oct 9 11:11:52 2021】Reading on book ...

------------------------

【Sat Oct 9 11:11:53 2021】all over.

Process finished with exit code 0

可以看到，在没有使用多线程的情况下，代码的调用是顺序的，在music()函数没有执行完之前，是不会执行read()函数的。

在Python中，有两个模块可以实现多线程：

thread
threading

其中，threading在thread的基础上，修复了一些缺陷，因此，直接使用threading就可以了。

代码：

from time import ctime, sleep
import threading

def music(name):
    for i in range(3):
        print("【%s】Listening to music ...[%s]\n" % (ctime(),name))
        sleep(1)

def read(name):
    for i in range(5):
        print("【%s】Reading on book ...[%s]\n" % (ctime(),name))
        sleep(4)

if __name__ == "__main__":

    # 没有多线程处理的情况下，代码是顺序执行的，前一个没有执行完是不会执行下一个的

    # music()
    # read()
    # print("------------------------")
    # print("【%s】all over." % ctime())

    # 多线程处理代码

    threads = []
    thread1 = threading.Thread(
        target=music,
        args=('歌白帝',)
    )
    threads.append(thread1)

    thread2 = threading.Thread(
        target=read,
        args=('道德情操论',)
    )
    threads.append(thread2)

    for t in threads:
        t.setDaemon(True)
        t.start()

    for t in threads:
        t.join()

    print("")
    print("------------------------")
    print("【%s】all over." % ctime())

from time import ctime, sleep

import threading

def music(name):

for i in range(3):

print("【%s】Listening to music ...[%s]\n" % (ctime(),name))

sleep(1)

def read(name):

for i in range(5):

print("【%s】Reading on book ...[%s]\n" % (ctime(),name))

sleep(4)

if __name__ == "__main__":

# 没有多线程处理的情况下，代码是顺序执行的，前一个没有执行完是不会执行下一个的

# music()

# read()

# print("------------------------")

# print("【%s】all over." % ctime())

# 多线程处理代码

threads = []

thread1 = threading.Thread(

target=music,

args=('歌白帝',)

)

threads.append(thread1)

thread2 = threading.Thread(

target=read,

args=('道德情操论',)

)

threads.append(thread2)

for t in threads:

t.setDaemon(True)

t.start()

for t in threads:

t.join()

print("")

print("------------------------")

print("【%s】all over." % ctime())

执行效果：

D:\adamhuan_data\pycharm_data\python_Multi_Threads\venv\Scripts\python.exe D:/adamhuan_data/pycharm_data/python_Multi_Threads/multi_threads.py
【Sat Oct  9 11:53:02 2021】Listening to music ...[歌白帝]

【Sat Oct  9 11:53:02 2021】Reading on book ...[道德情操论]

【Sat Oct  9 11:53:03 2021】Listening to music ...[歌白帝]

【Sat Oct  9 11:53:04 2021】Listening to music ...[歌白帝]

【Sat Oct  9 11:53:06 2021】Reading on book ...[道德情操论]

【Sat Oct  9 11:53:10 2021】Reading on book ...[道德情操论]

【Sat Oct  9 11:53:14 2021】Reading on book ...[道德情操论]

【Sat Oct  9 11:53:18 2021】Reading on book ...[道德情操论]


------------------------
【Sat Oct  9 11:53:22 2021】all over.

Process finished with exit code 0