Python3多线程如何为？
摘要：简单实现多线程 import threading import time def sing(sing): for i in range(5): print(" sing() {}".for
简单实现多线程
import threading
import time
def sing(sing):
for i in range(5):
print("---sing()---{}".format(sing))
time.sleep(1)
def dance(dance):
for i in range(5):
print("---dance()---{}".format(dance))
time.sleep(1)
def main():
t1 = threading.Thread(target=sing,args=("t1",))
t2 = threading.Thread(target=dance,args=("t2",))
t1.start()
t2.start()
if __name__ == "__main__":
main()
多线程互斥锁
import threading
import time
A = 2
lock = threading.Lock()
#创建一个互斥锁
def sing(sing):
global A
for i in range(500000):
lock.acquire()
#加锁
A += 1
lock.release()
#解锁
print('{}:{}'.format(sing,i))
def dance(dance):
global A
for i in range(500000):
lock.acquire()
#加锁
A -= 1
lock.release()
#解锁
print('{}:{}'.format(dance,i))
def main():
global A
t1 = threading.Thread(target=sing,args=("t1",))
t2 = threading.Thread(target=dance,args=("t2",))
t1.start()
t2.start()
t1.join()
t2.join()
print(A)
if __name__ == "__main__":
main()
查看线程数量
使用
threading.enumerate()
获取当前所有线程。
此处打印出一个列表，列表中共有3个线程信息。一个是主线程，另外两个是子线程
这里需要注意，我们需要在代码中使用join()方法来阻塞主线程。当所有阻塞的子线程执行完毕后，才会继续执行主线程。
通过继承Thread类，重写run方法实现多线程
import threading
import time
A = 2
lock = threading.Lock()
#创建一个互斥锁
class my_thread(threading.Thread):
def run(self) -> None:
self.sing()
def sing(self):
global A
if self._kwargs['mothed'] == 'add':
tmp = 1
elif self._kwargs['mothed'] == 'del':
tmp = -1
else:
tmp = 1
for i in range(50):
lock.acquire()
#加锁
A += tmp
lock.release()
#解锁
print('{}:{}:{}'.format(self._kwargs['cs'],i,A))
def main():
global A
t1 = my_thread(kwargs={'cs':'sing','mothed':'add'},name="T1")
t2 = my_thread(kwargs={'cs':'dance','mothed':'del'},name="T2")
t1.start()
t2.start()
print(threading.enumerate())
print(A)
t1.join()
t2.join()
print(A)
if __name__ == "__main__":
main()
多线程UDP聊天器
import threading
import socket
class my_thread(threading.Thread):
def run(self) -> None:
if self._kwargs['mothed'] == 'recv_message':
self.recv_message()
elif self._kwargs['mothed'] == 'send_message':
self.send_message()
def send_message(self):
while True:
try:
ip = input("目标IP:")
port = int(input("目标端口:"))
msg = input("发送的消息:").encode('utf-8')
except:
continue
self._kwargs['udp_socket'].sendto(msg,(ip,port))
def recv_message(self):
while True:
data,client_addr = self._kwargs['udp_socket'].recvfrom(1024)
print('source:', client_addr,'收到的数据：', data.decode("UTF-8"))
def main():
udp_socket = socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
udp_socket.bind(("",20216))
recv_message = my_thread(kwargs={'udp_socket':udp_socket,'mothed':'recv_message'},name="recv_message")
send_message = my_thread(kwargs={'udp_socket':udp_socket,'mothed':'send_message'},name="send_message")
recv_message.start()
send_message.start()
recv_message.join()
send_message.join()
if __name__ == "__main__":
main()