1.多線程技術(shù)1
python內(nèi)置的threading模塊,可以支持多線程
所有的進(jìn)程默認(rèn)都有一個(gè)線程(一般叫這個(gè)線程為主線程),其他的線程叫子線程
如果想要在進(jìn)程中添加其他的線程,就創(chuàng)建線程對(duì)象
import threading
import time
def download(file, time1):
print('開(kāi)始下載',file)
time.sleep(time1)
print(file, '下載結(jié)束')
1.創(chuàng)建線程對(duì)象
target: 需要在子線程中執(zhí)行的函數(shù)
args: 調(diào)用函數(shù)的實(shí)參列表(參數(shù)類型是列表)
返回值: 線程對(duì)象
t1 = threading.Thread(target=download, args=['愛(ài)情公寓', 10])
# 2.在子線程中執(zhí)行任務(wù)
t1.start()
t2 = threading.Thread(target=download, args=['狄仁杰', 5])
t2.start()
# download('愛(ài)情公寓')
# download('狄仁杰')
print('=====')
# t3 = threading.Thread(target=input, args=['>>>'])
# t3.start()
value = input('>>>')
print('!!!!')
2.多線程技術(shù)
方式2:寫(xiě)一個(gè)自己的線程類
1.寫(xiě)一個(gè)類,繼承自Thread類
2.重寫(xiě)run方法,在里面規(guī)定需要在子線程中執(zhí)行的任務(wù)
3.實(shí)現(xiàn)在子線程中執(zhí)行的任務(wù)對(duì)應(yīng)的功能,如果需要參數(shù),通過(guò)類的對(duì)象屬性來(lái)傳值
"""
from threading import Thread
import requests
import re
下載數(shù)據(jù)
class DownloadThread(Thread):
"""下載類"""
def init(self, file_path):
super().init()
self.file_path = file_path
def run(self):
"""run方法"""
"""
1.寫(xiě)在這個(gè)方法的內(nèi)容就是在子線程中執(zhí)行的內(nèi)容
2.這個(gè)方法不要直接調(diào)用
"""
print('開(kāi)始下載')
response = requests.request('GET', self.file_path)
data = response.content
# 獲取文件后綴
suffix = re.search(r'\.\w+$', self.file_path).group()
with open('./abc'+suffix, 'wb') as f:
f.write(data)
print('下載完成...')
if name == 'main':
print('=====')
t1 = DownloadThread('http://10.7.181.117/shareX/Git.exe')
# 通過(guò)start間接調(diào)用run方法,run方法中的任務(wù)在子線程中執(zhí)行
t1.start()
# 直接調(diào)用run方法,run方法中的任務(wù)在當(dāng)前線程中執(zhí)行
# t1.run()
t2 = DownloadThread('https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1533720058151&di=766b5c97653351e805c85881ecaa57d0&imgtype=0&src=http%3A%2F%2Fx.itunes123.com%2Fuploadfiles%2Fb2ab55461e6dc7a82895c7425fc89017.jpg')
t2.start()
print('!!!!!')
3.多線程技術(shù)
import socket
from threading import Thread
class CoversationThread(Thread):
"""在子線程中處理不同的客戶端會(huì)話"""
"""
python中可以在函數(shù)參數(shù)的后面加一個(gè)冒號(hào),來(lái)對(duì)參數(shù)的類型進(jìn)行說(shuō)明
"""
def __init__(self, conversation:socket.socket, address):
super().__init__()
self.conversation = conversation
self.address = address
def run(self):
while True:
self.conversation.send('你好!'.encode())
print(self.address,self.conversation.recv(1024).decode(encoding='utf-8'))
if __name__ == '__main__':
server = socket.socket()
server.bind(('10.7.181.117', 8080))
server.listen(512)
while True:
conversation, address = server.accept()
t = CoversationThread(conversation, address)
t.start()
# while True:
# conversation.send('你好!'.encode())
# print(conversation.recv(1024).decode(encoding='utf-8'))
4.join函數(shù)
from threading import Thread,currentThread
import time
from random import randint
class Download(Thread):
def __init__(self, file):
# 這兒父類的init方法必須調(diào)用,否則當(dāng)前這個(gè)創(chuàng)建的對(duì)象中就沒(méi)有新的線程
super().__init__()
self.file = file
def run(self):
print(currentThread())
print('開(kāi)始下載:%s' % self.file)
time.sleep(randint(5, 10))
print('%s下載結(jié)束' % self.file)
if __name__ == '__main__':
# time.time(): 獲取當(dāng)前時(shí)間-時(shí)間戳
start_time = time.time()
t1 = Download('最強(qiáng)Z.mp4')
t1.start()
t2 = Download('最強(qiáng)A.mp4')
t2.start()
print('====')
# 獲取當(dāng)前線程
"""
主線程: MainThread
子線程: Thread-數(shù)字(數(shù)字從1開(kāi)始。)
"""
print(currentThread())
# 如果一個(gè)任務(wù)想要在另外一個(gè)子線程中的任務(wù)執(zhí)行完成后再執(zhí)行,就在當(dāng)前任務(wù)前用子線程對(duì)象調(diào)用join方法
# 所以join也會(huì)阻塞線程,阻塞到對(duì)應(yīng)的子線程中任務(wù)執(zhí)行完為止
t1.join()
# t2.join()
end_time = time.time()
print('總共消耗時(shí)間:%.2f' % (end_time - start_time))
5.耗時(shí)間操作
import pygame
from random import randint
import time
"""
1.耗時(shí)操作放到主線程中的問(wèn)題:
耗時(shí)操作放到主線程中,會(huì)阻塞線程
多個(gè)耗時(shí)操作都放到一個(gè)線程中執(zhí)行,最終執(zhí)行的時(shí)間是兩個(gè)耗時(shí)操作的時(shí)間和
2.怎么解決問(wèn)題?
使用多線程(創(chuàng)建多個(gè)線程)
"""
def rand_color():
return randint(0, 255),randint(0, 255),randint(0, 255)
def long_time():
print('耗時(shí)操作開(kāi)始')
time.sleep(10)
print('耗時(shí)操作結(jié)束')