C++ 网络编程 socket 数据报文封装一次性发送

在数据报文的基础上，将数据一次性发送过去，减少出错的几率；

server

// ctrl + k + c // Ctrl + K+ U #define WIN32_LEAN_AND_MEAN #include <iostream> #include <Windows.h> #include <WinSock2.h> using namespace std; //加入静态连接库 #pragma comment(lib,"ws2_32.lib") //输出目录 $(SolutionDir)..bin/$(Platform)/$(Configuration)\ //中间目录 $(SolutionDir)../temp/$(Platform)/$(Configuration)/$(ProjectName)\ enum CMD { CMD_LOGIN, CMD_LOGIN_RESULT, CMD_LOGOUT, CMD_LOGOUT_RESULT, LOG_ERROR }; //消息头 struct DataHeader { short dataLength;//数据长度 short cmd;// }; //DataPackage struct Login :public DataHeader { Login() { dataLength = sizeof(Login); cmd = CMD_LOGIN; } /*Login(char *name, char *pwd) { strcpy(userName, name); strcpy(PassWord, pwd); }*/ char userName[32]; char PassWord[32]; }; struct LoginResult :public DataHeader { LoginResult() { dataLength = sizeof(LoginResult); cmd = CMD_LOGIN_RESULT; result = 0; } int result; }; struct LogOut :public DataHeader { LogOut() { dataLength = sizeof(LogOut); cmd = CMD_LOGOUT; } /*LogOut(char *name) { strcpy(userName, name); }*/ char userName[32]; }; struct LogOutResult :public DataHeader { LogOutResult() { dataLength = sizeof(LogOutResult); cmd = CMD_LOGIN_RESULT; result = 0; } int result; }; int main() { //启动windows socket 2.x环境 WORD ver = MAKEWORD(2, 2); WSADATA dat; WSAStartup(ver, &dat); //--------------------------- //TCP 服务端 //启动windows scoket编程环境 //1.建立一个socket SOCKET _sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); //ipv4 数据流 TCP //2.绑定接受客户端连接的端口号bind sockaddr_in _sin = {};// _sin.sin_family = AF_INET;//网络类型 ipv4 _sin.sin_port = htons(4567);// host to net unsigned short 端口号 主机数据转换到网络数据，无符号数据类型 _sin.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");// 服务器的ip地址 //当不知道自己的本机ip地址时可以写为 INADDR_ANY if (bind(_sock, (sockaddr*)&_sin, sizeof(_sin)) == SOCKET_ERROR) { cout << "绑定用于接收客户端连接的网络端口失败" << endl; } else { cout << "绑定网络端口成功..." << endl; }//网络端口是否被占用 //3.监听网络端口listen if (listen(_sock, 5) == SOCKET_ERROR)//等待连接的队列的长度 { cout << "监听网络端口失败..." << endl; } else { cout << "监听网络端口成功..." << endl; } //4.等待接受客户端连接accept sockaddr_in clientAddr = {};//客户端的地址和端口 int nAddrLen = sizeof(sockaddr_in); SOCKET _cSock = INVALID_SOCKET; _cSock = accept(_sock, (sockaddr *)&clientAddr, &nAddrLen); if (_cSock == INVALID_SOCKET) { cout << "错误，接收到无效客户端SOCKET..." << endl; } else { cout << "接收数据客户端有效..." << endl; } cout << "新客户端加入: socket = " << _cSock << ", IP = " << inet_ntoa(clientAddr.sin_addr) /*转换为 字符串 刻度的字符串数字*/ << endl; while (true) { DataHeader header = {}; //5.接收客户端的请求数据 int nLen = recv(_cSock,(char*)&header, sizeof(DataHeader), 0); if (nLen <= 0) { cout << "客户端已退出，任务结束" << endl; break; } //6.处理请求 switch (header.cmd) { case CMD_LOGIN: { Login login = {}; //做数据的偏移 recv(_cSock, (char*)&login + sizeof(DataHeader), sizeof(Login) - sizeof(DataHeader), 0); cout << "收到命令：数据命令：" << login.cmd << "，数据长度：" << login.dataLength << "，userName = " << login.userName << ",PassWord = " << login.PassWord << endl; LoginResult ret; //忽略判断用户名和密码是否正确 send(_cSock, (char*)&ret, sizeof(LoginResult), 0); } break; case CMD_LOGOUT: { LogOut logOut = {}; recv(_cSock, (char*)&logOut + sizeof(DataHeader), sizeof(LogOut) - sizeof(DataHeader), 0); cout << "收到命令：数据命令：" << logOut.cmd << "，数据长度：" << logOut.dataLength << "，userName = " << logOut.userName << endl; LogOutResult ret; //忽略判断用户名和密码是否正确 send(_cSock, (char*)&ret, sizeof(LogOutResult), 0); } break; default: { header.cmd = LOG_ERROR; header.dataLength = 0; send(_cSock, (char *)&header, sizeof(header), 0);//strlen(msgBuf) + 1 将结尾符一并发送过去 break; } } } //8.关闭socket closesocket closesocket(_sock); //---------------------------- //清除windows socket环境 WSACleanup(); getchar(); return 0; }

client

#define WIN32_LEAN_AND_MEAN #include <iostream> #include <Windows.h> #include <WinSock2.h> using namespace std; //加入静态连接库 #pragma comment(lib,"ws2_32.lib") //输出目录 $(SolutionDir)..bin/$(Platform)/$(Configuration)\ //中间目录 $(SolutionDir)../temp/$(Platform)/$(Configuration)/$(ProjectName)\ enum CMD { CMD_LOGIN, CMD_LOGIN_RESULT, CMD_LOGOUT, CMD_LOGOUT_RESULT, LOG_ERROR }; //消息头 struct DataHeader { short dataLength;//数据长度 short cmd;// }; //DataPackage struct Login:public DataHeader { Login() { dataLength = sizeof(Login); cmd = CMD_LOGIN; } /*Login(char *name, char *pwd) { strcpy(userName, name); strcpy(PassWord, pwd); }*/ char userName[32]; char PassWord[32]; }; struct LoginResult :public DataHeader { LoginResult() { dataLength = sizeof(LoginResult); cmd = CMD_LOGIN_RESULT; result = 0; } int result; }; struct LogOut :public DataHeader { LogOut() { dataLength = sizeof(LogOut); cmd = CMD_LOGOUT; } /*LogOut(char *name) { strcpy(userName, name); }*/ char userName[32]; }; struct LogOutResult :public DataHeader { LogOutResult() { dataLength = sizeof(LogOutResult); cmd = CMD_LOGIN_RESULT; result = 0; } int result; }; int main() { //启动windows socket 2.x环境 WORD ver = MAKEWORD(2, 2); WSADATA dat; WSAStartup(ver, &dat); //----------------------------- //TCP客户端 //1.建立一个socket SOCKET _sock = socket(AF_INET, SOCK_STREAM, 0); if (_sock == INVALID_SOCKET) { cout << "连接服务器失败..." << endl; } else { cout << "连接服务器成功.." << endl; } //2.连接服务器connect sockaddr_in _sin = {}; _sin.sin_family = AF_INET; _sin.sin_port = htons(4567); _sin.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");//声明服务端地址 int ret = connect(_sock, (sockaddr*)(&_sin), sizeof(sockaddr_in)); if (ret == SOCKET_ERROR) { cout << "连接服务器失败" << endl; } else { cout << "连接服务器成功" << endl; } while (true) { //3.输入请求命令 char cmdBuf[128] = {}; //cin >> cmdBuf; scanf("%s", cmdBuf); //4.处理请求 //5.把命令发送给服务端 if (strcmp(cmdBuf, "exit") == 0) { cout << "已退出客户端，任务结束！" << endl; break; } else if (strcmp(cmdBuf, "login") == 0) { Login login/*{ "jmm","lovely" }*/; strcpy(login.userName, "jmm"); strcpy(login.PassWord, "lovely"); //5.把命令发送给服务端 send(_sock, (char *)&login, sizeof(login), 0); // 接受服务器返回的数据 LoginResult loginRet = {}; recv(_sock, (char*)&loginRet, sizeof(loginRet), 0); cout << "LoginResult: " << loginRet.result << endl; } else if (strcmp(cmdBuf, "logout") == 0) { LogOut logout;//("jmm"); strcpy(logout.userName, "jmm"); //5.把命令发送给服务端 send(_sock, (char *)&logout, sizeof(logout), 0); // 接受服务器返回的数据 LoginResult logoutRet; recv(_sock, (char*)&logoutRet, sizeof(logoutRet), 0); cout << "LogOutResult: " << logoutRet.result << endl; } else { cout << "不支持该命令，请重新输入！" << endl; } } //7.关闭socket closesocket closesocket(_sock); //---------------------------- //清除windows socket环境 WSACleanup(); getchar(); return 0; }

运行结果