import socket "服务器端" server = socket.socket() # 生成连接对象 server.bind(("localhost",6000)) # 绑定要监听的端口 server.listen(5) # 开始监听（最大允许挂起的连接） while True: print("\n服务器在等待...") conn,addr = server.accept() # 等待客户端发起建立连接，起到阻塞作用 # conn 是客户端链接过来而在服务器端为其生成的连接实例，addr是IP地址+端口 print("已成功连接") print("连接对象：{0}，地址：{1}\n".format(conn,addr)) while True: try: data = conn.recv(1024) # 接收数据 # (如果客服端断开连接，此步骤将会被无限循环操作，所以一定要有检查机制) if data != b"000001": # 接收到的信号不是"000001"的话就正常执行 print("接收客户端信息：", data.decode()) msg = input(">>输入返回客户端的数据：") conn.send(msg.encode(encoding="utf-8")) # 向客户端发送数据 else: print("该客户已主动断开连接") break except ConnectionResetError as e: print("该客户机异常！已被强迫断开连接",e) break else: print("It's OK !") server.close()

import socket "通信案例客户端消息接收与发送" client = socket.socket() # 声明socket类型，并生成socket连接对象 try: client.connect(("localhost",6000)) # 与服务器建立连接 while True: msg = input(">>输入要向服务器发送的信息：") client.send(msg.encode(encoding="utf-8")) # 向服务器发送信息(只能发送bytes字节类型，不能是str字符类型) data = client.recv(1024) # 接收来自服务器的1024个字节 print("接收来自服务器的数据：",data.decode()) # 打印服务器发送的数据 chioce = input("按任意键继续，按0退出客户端") if chioce == "0": client.send(b"000001") # 发送此信号表明客户端要断开连接 break client.close() except ConnectionRefusedError as e: print("服务器还没开机！请静候")

import socket,os,hashlib ser = socket.socket() ser.bind(("localhost",5000)) ser.listen() while True: try: print("正在等待客户端连接...") conn,addr = ser.accept() print("已连接，new conn:",addr) while True: data = conn.recv(8192) filename = data.decode() print("寻找文件",filename) if os.path.isfile(filename): conn.send(b"01") conn.recv(1024) f = open(filename,"rb") m = hashlib.md5() file_size = os.stat(filename).st_size conn.send(str(file_size).encode(encoding="utf-8")) client_ack = conn.recv(1024) # 接收确认信息 if client_ack == b"1": print("开始发送数据") for line in f: m.update(line) conn.send(line) f.close() conn.send(m.hexdigest().encode(encoding="utf-8")) # 发送MD5值 else: conn.send(b"00") #表示文件不存在 print("该文件不存在！") except ConnectionResetError: print("该客户端已断开连接") ser.close() print("服务器已关闭")

import socket,hashlib def receive1(client): "真正的数据接收" while True: res = b"" res = res + client.recv(1024) return res def receive(client,filename): "接收处理" m = hashlib.md5() rece_res_size = int(client.recv(1024).decode()) # 接收的结果长度，转成int型 client.send(b"1") rece_size = 0 res = b"" filename = filename.decode() f = open(filename + ".new","wb") while rece_size < rece_res_size: if rece_res_size - rece_size >1024: # 如果不是最后一次接收数据 size = 1024 else: # 最后一次接收数据 size = rece_res_size - rece_size a = client.recv(size) # 循环接收数据 res = res + a rece_size = len(res) m.update(a) f.write(a) print("发送数据量:{0}，接收数据量:{1}".format(rece_res_size,rece_size)) else: serves_md5 = client.recv(1024).decode() print("服务器MD5：",serves_md5) print("客户端MD5：",m.hexdigest()) if serves_md5 == m.hexdigest(): print("文件接收并校验完毕！") res.decode() f.close() def main(): client = socket.socket() try: client.connect(("localhost", 5000)) while True: filename = input("请输入需要的文件名").strip().encode(encoding="utf-8") if len(filename) == 0: print("输入为空，重新输入") continue client.send(filename) is_file = client.recv(1024) if is_file == b"01": client.send(b"OK") receive(client,filename) # 调用函数接收数据，返回结果res（bytes） else: print(" {0} 文件不存在！".format(filename.decode())) except ConnectionRefusedError: print("等待服务器开机") client.close() main()

import socketserver ''' 每一个客户端请求过来，都会实例化 MyTCPHandler ''' class MyTCPHandler(socketserver.BaseRequestHandler): def handle(self): "跟客户端所有的交互都是在handle里完成的" while True: try: self.data = self.request.recv(1024).strip() print("{0} wrote:".format(self.client_address[0])) print(self.data) if not self.data: print("输入为空") self.request.send(bytes("输入为空", "utf-8")) else: self.request.send(self.data.upper()) except ConnectionResetError : print("客户已断开连接") break if __name__ == "__main__": HOST, PORT = "localhost", 9999 #server = socketserver.TCPServer((HOST, PORT), MyTCPHandler) # 实例化一对一的连接对象 server = socketserver.ThreadingTCPServer((HOST, PORT), MyTCPHandler) # 实例化多并发的连接对象(多线程) server.serve_forever()

import socket HOST, PORT = "localhost", 9999 sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.connect((HOST, PORT)) while True: data = input("输入字符") try: sock.sendall(bytes(data + "\n", "utf-8")) received = str(sock.recv(1024), "utf-8") finally: print("Sent: {0}".format(data)) print("Received: {0}".format(received)) sock.close()