C++ 简单TCP实例

简单TCP原理如上篇所示。这里用一个简单的例子来演示流程的实现

Server与Client的区别在于

Server用bind, listen, accept，简称“绑听接”

Client用connect，简称“连”

1. 创建Win32控制台项目，加入SimpleTCPServer.cpp

/* *一问一答式简单TCP短连接,用于演示TCP连接原理 */#pragma comment (lib, "ws2_32.lib")#pragma warning (disable: 4267)#include <WinSock2.h>#include <stdio.h>void main(){//变量声明char sBuffer[1024];SOCKET socketServer;sockaddr_in addrServer;SOCKET socketClient;sockaddr_in addrClient;int addrSize = sizeof(addrClient);WSADATA wsaData;WORD wVersionRequested;//Socket环境初始化wVersionRequested = MAKEWORD(2, 2);int nRes = WSAStartup(wVersionRequested, &wsaData);if(nRes != 0){return;}//创建服务器SocketsocketServer = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);if (socketServer == INVALID_SOCKET){return;}//服务器地址配置addrServer.sin_family = AF_INET;addrServer.sin_addr.s_addr = INADDR_ANY;addrServer.sin_port = htons(6000);//绑定Socket与地址if(bind(socketServer, (sockaddr*)&addrServer, sizeof(addrServer)) == SOCKET_ERROR){return;}//最多监听10个客户端if (listen(socketServer, 10) == SOCKET_ERROR) {return;}printf("服务器启动成功!\n");//等待客户端请求while (true){printf("等待客户端接入...\n");//接受客户端连接socketClient = accept(socketServer, (sockaddr*)&addrClient, &addrSize);if (socketClient == INVALID_SOCKET){continue;}printf("客户端连接成功: %s\n", inet_ntoa(addrClient.sin_addr));//接收客户端消息memset(sBuffer, 0, sizeof(sBuffer));nRes = recv(socketClient, sBuffer, sizeof(sBuffer), 0);if (nRes == SOCKET_ERROR){continue;}printf("它说: %s\n", sBuffer);//向客户端发送消息memset(sBuffer, 0, sizeof(sBuffer));sprintf(sBuffer, "连接到服务器");nRes = send(socketClient, sBuffer, strlen(sBuffer) + 1, 0);if (nRes == SOCKET_ERROR){continue;}//关闭客户端连接closesocket(socketClient);}//关闭服务器连接closesocket(socketServer);//清除Socket环境WSACleanup();}

2. 创建Win32控制台项目，加入SimpleTCPClient.cpp

/* *一问一答式简单TCP短连接,用于演示TCP连接原理 */#pragma comment (lib, "ws2_32.lib")#pragma warning (disable: 4267)#include <WinSock2.h>#include <stdio.h>void main(){//变量声明char sBuffer[1024];SOCKET socketServer;sockaddr_in addrServer;WSADATA wsaData;WORD wVersionRequested;//Socket环境初始化wVersionRequested = MAKEWORD(2, 2);int nRes = WSAStartup(wVersionRequested, &wsaData);if(nRes != 0){return;}//创建服务器SocketsocketServer = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);if (socketServer == INVALID_SOCKET){WSACleanup();return;}//服务器地址配置addrServer.sin_family = AF_INET;addrServer.sin_addr.s_addr = inet_addr("127.0.0.1");addrServer.sin_port = htons(6000);//连接服务器Socket与地址if(connect(socketServer, (sockaddr*)&addrServer, sizeof(addrServer)) == SOCKET_ERROR){closesocket(socketServer);WSACleanup();return;}//向服务端发送消息memset(sBuffer, 0, sizeof(sBuffer));sprintf(sBuffer, "你好!");nRes = send(socketServer, sBuffer, strlen(sBuffer) + 1, 0);if (nRes == SOCKET_ERROR){closesocket(socketServer);WSACleanup();return;}//接收服务端消息memset(sBuffer, 0, sizeof(sBuffer));nRes = recv(socketServer, sBuffer, sizeof(sBuffer), 0);if (nRes == SOCKET_ERROR){closesocket(socketServer);WSACleanup();return;}printf("%s%s\n", sBuffer, inet_ntoa(addrServer.sin_addr));//关闭客户端连接closesocket(socketServer);//清除Socket环境WSACleanup();system("pause");}

分别编译、运行Server和Client。