python3有threading和_thread两种线程写法,推荐使用threading。
开多线程就是为了使用多线程的异步能力来同时执行多个线程。
以下代码可以执行异步或者同步线程。
1 import threading
2 import time
3
4
5 class my_thread(threading.Thread):
6 def __init__(self, th_id, th_name):
7 threading.Thread.__init__(self)
8 self.th_id = th_id
9 self.th_name = th_name
10 pass
11
12 def run(self):
13 print("开始线程:" + self.th_name)
14 run_func(self.th_name)
15 print("退出线程:" + self.th_name)
16
17 pass
18
19
20 exitFlag = 0
21
22
23 def run_func(th_name):
24 if exitFlag:
25 th_name.exit()
26 pass
27 else:
28 # print('运行线程:' + th_name)
29 do(th_name)
30 pass
31 print('---%s---' % (time.ctime(time.time())))
32 # time.sleep(0.1)
33 pass
34
35
36 # 自定义,在此定义你要运行的参数
37 def do(th_name):
38 print('---执行自定义函数---')
39
40 pass
41
42
43 def index(sync):
44 print('开始创建线程。。')
45 for create in range(0, 2000):
46 # 创建新线程
47 th = my_thread(create, "Thread-" + str(create)) # id, name
48 th.start()
49 if sync: # 线程同步异步开关,True/False
50 th.join() # 线程等待,执行完才能进入下一个线程
51 pass
52 else: # 异步,推荐
53 pass
54 pass
55 print('\n所有线程创建完毕。。')
56 pass
57
58
59 index(False) # 同步线程True,异步线程False(推荐)
1 import _thread
2
3
4 all_thread_num = 0
5
6
7 def page_class(cla, that_num):
8 print("已启动线程=" + str(that_num))
9 global all_thread_num
10 all_thread_num += 1
11 print("线程总数=" + str(all_thread_num))
12 for page in range(1, 30):
13 print("内=" + str(page))
14 pass
15 pass
16
17
18 for cla in range(20190, 20291): # 创建线程
19 try:
20 _thread.start_new_thread(page_class, (cla, (cla - 20000)))
21 pass
22 except:
23 print("无法启动线程")
24 pass
25 pass
26
27 while 1:
28 pass