python 多线程 Threading

简单的多线程：python 2.7

# -*- coding: utf-8 -*-
import threading

def run_thread():
while True:
cmd = input("input you choice: ")
print(cmd)
if cmd == 0:
print("Thread Exit")
break
else:
print("Thread Running")

t1 = threading.Thread(target=run_thread)
t1.setDaemon(True)
t1.start()
print('join')
t1.join()
print('End')

运行结果:

input you choice: join
1
1
Thread Running
input you choice: 2
2
Thread Running
input you choice: 0
0
Thread Exit
End

Process finished with exit code 0

t1.join()的作用的是阻塞等待子线程t1退出，才返回往下执行

实验1

将t1.join() 这句注释掉：

# -*- coding: utf-8 -*-
import threading

def run_thread():
while True:
cmd = input("input you choice: ")
print(cmd)
if cmd == 0:
print("Thread Exit")
break
else:
print("Thread Running")

t1 = threading.Thread(target=run_thread)
t1.setDaemon(True)
t1.start()
print('join')
#t1.join()
print('End')

运行结果：

joininput you choice:
End

Process finished with exit code 0

主线程退出的时候，子线程也一起退出了

没有机会输入数据。

实验2：

将t1.join() 这句注释掉：

将t1.setDaemon(True) 这句也注释掉：

# -*- coding: utf-8 -*-
import threading

def run_thread():
while True:
cmd = input("input you choice: ")
print(cmd)
if cmd == 0:
print("Thread Exit")
break
else:
print("Thread Running")

t1 = threading.Thread(target=run_thread)
#t1.setDaemon(True)
t1.start()
print('join')
#t1.join()

运行结果：

joininput you choice:
End
1
1
Thread Running
input you choice: 2
2
Thread Running
input you choice: 5
5
Thread Running
input you choice: 0
0
Thread Exit

Process finished with exit code 0

主线程退出，子线程还在运行，还可以输入数据