threading示例

多线程举例：

import time
import threading
def worker():
    print ("hello.Kamil")
    time.sleep(1)#等待一秒
    return
time_start=time.time()
if __name__ == "__main__":
    for i in range(5):
        worker()#（执行五次）
time_end = time.time()
print(time_end-time_start)
for n in range(5):
    t = threading.Thread(target=worker)
    t.start()
time_end2 = time.time()

执行结果：

kamil@ubuntu-kamil:~/PycharmProjects/ftp0310/0310shangke/try$ python3. d.py
hello.Kamil
hello.Kamil
hello.Kamil
hello.Kamil
hello.Kamil
5.006033897399902
hello.Kamil
hello.Kamil
hello.Kamil
hello.Kamil
hello.Kamil
0.0030531883239746094
kamil@ubuntu-kamil:~/PycharmProjects/ftp0310/0310shangke/try$ 

第二次虽然也是循环5次，但是启用多线程来完成的，所以速度提升非常明显；

示例2：

import threading
import time
class timer(threading.Thread):
    def __init__(self, num, interval):
        threading.Thread.__init__(self)
        self.thread_num = num
        self.interval = interval
        self.thread_stop = False
    def run(self):
        while not self.thread_stop:
            print ('Thread Object(%s), Time:%s\n' %(self.thread_num, time.ctime())  )
            time.sleep(self.interval)
    def stop(self):
        self.thread_stop = True
def test():
    thread1 = timer('thread1',2)
    thread2 = timer('thread2',3)
    thread1.start()
    thread2.start()
    time.sleep(7)
    thread1.stop()
    thread2.stop()
    return
 
if __name__ == '__main__':
    test()

同时启动两个线程，thread1 与 thread2 ，其中1 是间隔2s 执行打印一次，2是间隔3s执行打印一次；在运行开始后，会在第六秒再次同时运行；结果如下：

kamil@ubuntu-kamil:~/PycharmProjects/ftp0310/0310shangke/try$ python3.4 c.py
Thread Object(thread1), Time:Thu Mar 17 09:27:26 2016                      1   26
 
Thread Object(thread2), Time:Thu Mar 17 09:27:26 2016                      2   26
 
Thread Object(thread1), Time:Thu Mar 17 09:27:28 2016　　　　　　　　　　　　　1   28
 
Thread Object(thread2), Time:Thu Mar 17 09:27:29 2016                      2   29
 
Thread Object(thread1), Time:Thu Mar 17 09:27:30 2016                      1   30
 
Thread Object(thread2), Time:Thu Mar 17 09:27:32 2016                      2   32
 
Thread Object(thread1), Time:Thu Mar 17 09:27:32 2016                      1   32
 
kamil@ubuntu-kamil:~/PycharmProjects/ftp0310/0310shangke/try$ 

threading.activeCount()的使用