线程数据安全
review
from threading import Thread
def func1():
print('子线程中执行')
t1 = Thread(target=func1, args=())
t1.start()
class YtThread(Thread):
def __init__(self):
super().__init__()
def run(self) -> None:
print('子线程中执行')
t2 = YtThread()
t2.start()
homewor服务器
from socket import *
from threading import *
import os
from json import *
class DealClientThread(Thread):
def __init__(self, connection: socket, address):
super().__init__()
self.connection = connection
self.address = address
def run(self) -> None:
while True:
re_data = self.connection.recv(1024)
message = re_data.decode('utf-8')
if message == 'text':
self.connection.send('我是文字信息!'.encode())
elif message == 'image':
all_files = os.listdir('./images')
# 发送所有的图片名字
self.connection.send(dumps(all_files).encode())
# 接收图片名
image_name = self.connection.recv(1024)
# 判断图片是否存在
image_path = './images/'+image_name.decode(encoding='utf-8')
if os.path.exists(image_path):
print('文件存在!')
self.connection.send('exists'.encode())
with open(image_path, 'rb') as f:
self.connection.send(f.read())
else:
print('文件不存在！')
self.connection.send('notExists'.encode())
else:
self.connection.close()
break
def creatServer():
server = socket()
server.bind(('10.7.181.109', 9997))
server.listen(512)
while True:
print('开始监听....')
connection, adderss = server.accept()
t = DealClientThread(connection, adderss)
t.start()
if __name__ == '__main__':
creatServer()
客户端
from socket import socket
from json import *
client = socket()
client.connect(('10.7.181.109', 9997))
while True:
print('1.获取文字信息\n2.获取图片信息\n3.退出')
value = input('请选择(1-3):')
if value == '1':
client.send('text'.encode())
# 接收服务器返回的文字信息
message_data = client.recv(1024)
print(message_data.decode(encoding='utf-8'))
elif value == '2':
client.send('image'.encode())
# 接收服务返回的所有的图片信息
image_message = client.recv(1024)
all_files = loads(image_message.decode(encoding='utf-8'))
for index in range(len(all_files)):
print('%d: %s' % (index, all_files[index]))
# 选择需要的图片
num = int(input('请选择需要的图片名(0-%d):' % len(all_files)))
# 发送图片名
client.send(all_files[num].encode())
# 接收图片
is_exsits = (client.recv(1024)).decode(encoding='utf-8')
if is_exsits == 'exists':
image_data = bytes() # 创建空的二进制
while True:
small_image_data = client.recv(1024)
image_data += small_image_data
if len(small_image_data) < 1024:
break
with open('./client/'+all_files[num], 'wb') as f:
f.write(image_data)
print('图片下载完成!')
else:
print('404，图片不存在！')
else:
client.send('exit'.encode())
client.close()
break
线程间数据共享
from threading import Thread
总结: 数据的存储跟线程无关;一个进程中的数据在多个线程中可以直接用
情况一: 在子线程中使用主线程中的数据
# list1 = [1, 2, 3]
#
#
# def func1():
# list1.append(100)
#
#
# def func2():
# list1[0] = 'hello'
#
#
# t1 = Thread(target=func1)
# t2 = Thread(target=func2)
# t1.start()
# t2.start()
#
# t1.join()
# t2.join()
# print(list1) # ['hello', 2, 3, 100]
# 情况2: 在子线程中使用子线程中产生的数据
def func1():
global list1
list1 = [1, 2, 3]
def func2():
t = Thread(target=func1)
t.start()
print(list1)
t1 = Thread(target=func2)
t1.start()
数据共享安全性问题
from time import sleep
from threading import Thread, Lock
获取锁对象
获取数据
数操作完成后
释放锁对象
注意: 使用锁的时候保证一个数据对应一把锁
class Account:
"""银行账号类"""
def __init__(self, name, tel, balance, bank='招商银行'):
self.bank = bank
self.card_number = '6233392838382383'
self.name = name
self.tel = tel
self.balance = balance
self.lock = Lock() # 1.创建锁(保证一个数据一把锁)
def save_money(self, amount):
print('=====开始存钱！======')
# 2.使用锁
self.lock.acquire()
# 获取余额
bl = self.balance
# print('存钱余额1:',bl)
sleep(2)
self.balance = bl + amount
# 3.释放锁
self.lock.release()
# print('存钱余额2:', self.balance)
print('=====存钱结束!======')
def draw_money(self, amount):
print('=====开始取钱！======')
self.lock.acquire()
bl = self.balance
# print('取钱余额1:', bl)
if bl < amount:
print('余额不足!')
print('=====取钱结束======')
return
sleep(3)
self.balance = bl - amount
self.lock.release()
# print('取钱余额2:', self.balance)
print('=====取钱结束======')
account = Account('余婷', '153000782', 10000)
t1 = Thread(target=account.save_money, args=(20000,))
t2 = Thread(target=account.draw_money, args=(5000,))
t1.start()
t2.start()
t1.join()
t2.join()
print(account.balance)
account2 = Account('小明', '23782738738', 1000)
锁的使用
from threading import *
from time import sleep
list1 = [1, 2, 3]
lock = Lock()
def func1():
lock.acquire()
global list1
list2 = list1[:]
sleep(3)
list2.append(100)
list1 = list2[:]
lock.release()
def func2():
lock.acquire()
global list1
list2 = list1[:]
sleep(3)
list2.remove(2)
list1 = list2[:]
lock.release()
t1 = Thread(target=func1)
t2 = Thread(target=func2)
t1.start()
t2.start()
t1.join()
t2.join()
print(list1)
