一、UDP 数据报协议

特点：

①客户端允许发空————默认有报头

②协议不会粘包

③在服务端不存在的情况下，客户端不会报错

④udp 协议支持并发效果

注：udp在启动服务之后，只能被动等待客户端发消息，客户端发送消息是需要带上服务端地址

       同理，在服务端回消息是也要带上客户端地址

示例：

import socketserver = socket.socket(type=socket.SOCK_DGRAM)server.bind(('127.0.0.1', 8080))msg, addr = server.recvfrom(1024)print(msg.decode('utf-8'))server.sendto(b'hello', addr)server.close()

import socketclient = socket.socket(type=socket.SOCK_DGRAM)server_addr = ('127.0.0.1', 8080)client.sendto(b'hello server baby!', server_addr)msg, addr = client.recvfrom(1024)print(msg, addr)

总结：

TCP协议就类似于打电话UDP 协议就类似于发短信

二、SocketServer模块介绍（让tcp也能支持并发）

1、基于tcp协议的SocketServer：

import socketserverclass MyBaby(socketserver.BaseRequestHandler):    def handle(self):        # 通信循环        while True:            # self.request相当于你的conn通信对象            data,sock = self.request # 收消息            print(data)            sock.sendto(data.upper(),self.client_address)  # self.client_address客户端地址if __name__ == '__main__':    server = socketserver.ThreadingUDPServer(('127.0.0.1',8080),MyBaby)    server.serve_forever()

import socketclient = socket.socket()client.connect(('127.0.0.1',8080))while True:    client.send(b'hello')    data = client.recv(1024)    print(data)

2、基于udp协议的SocketServer：

import socketserverclass MyBaby(socketserver.BaseRequestHandler):    def handle(self):        # 通信循环        while True:            # self.request相当于你的conn通信对象            data,sock = self.request # 收消息            print(data)            sock.sendto(data.upper(),self.client_address)  # self.client_address客户端地址

import socketimport timeclient = socket.socket(type=socket.SOCK_DGRAM)sever_addr = ('127.0.0.1',8080)while True:    client.sendto(b'hello',sever_addr)    data,addr = client.recvfrom(1024)    print(data,addr)    time.sleep(1)