Python--多线程

import threading
import time
import requests


def say_hi(name):
    time.sleep(2)
    print(name)


def down_html(url1, name):
    res = requests.get(url1).content
    with open(name + '.html', 'wb') as f:
        f.write(res)


urls = [
    ['nnzhp', 'http://www.nnzhp.cn'],
    ['dsx', 'http://www.imdsx.cn'],
    ['besttest', 'http://www.besttest.cn']
]

start_time = time.time()
# for url in urls:
#     down_html(url[1], url[0])

threads = []  # 存放刚才启动的线程
for url in urls:
    t = threading.Thread(target=down_html, args=(url[1], url[0]))
    t.start()
    threads.append(t)
for t in threads:
    t.join()  # 主线程等待子线程结束
end_time = time.time()
print(end_time - start_time)

# for i in range(10):
#     t = threading.Thread(target=say_hi, args=('小黑',))  # 启动线程
#     t.start()

100个url,启动5个线程

import threading
import time

urls = list(range(100))


def p(url):
    for u in url:
        print(u)


start = 0
end = 20

for i in range(5):
    url_new = urls[start:end]
    start += 20
    end += 20
    t = threading.Thread(target=p, args=(url_new,))
    t.start()