1.多线程对于计算密集型无用
需求:列表li1每个元素加1,列表li2每个元素加100
# 导入模块
import threading
li1 = [11, 22, 33] # +1
li2 = [44, 55, 66] # 100
def func(data, plus):
for i in range(len(data)):
data[i] = data[i] + plus
# 线程1:负责给li1每个元素加1
t1 = threading.Thread(target=func, args=(li1, 1))
t1.start()
# 线程2:负责给li2每个元素加100
t2 = threading.Thread(target=func, args=(li2, 100))
t2.start()
2.多线程对于IO操作有用
# 导入模块
import threading
import uuid
import requests
# 图片地址列表
url_list = [
'https://www3.autoimg.cn/newsdfs/g28/M05/F9/98/120x90_0_autohomecar__ChsEnluQmUmARAhAAAFES6mpmTM281.jpg',
'https://www2.autoimg.cn/newsdfs/g28/M09/FC/06/120x90_0_autohomecar__ChcCR1uQlD6AT4P3AAGRMJX7834274.jpg',
'https://www2.autoimg.cn/newsdfs/g3/M00/C6/A9/120x90_0_autohomecar__ChsEkVuPsdqAQz3zAAEYvWuAspI061.jpg',
]
def task(img_url):
ret = requests.get(img_url)
file_name = str(uuid.uuid4()) + '.jpg'
with open(file_name, mode='wb') as f:
f.write(ret.content)
for url in url_list:
t = threading.Thread(target=task, args=(url,))
t.start()