【C++】创建TCP服务端

实现了一个基本的 TCP 服务器，可以接受多个客户端连接，然后持续接收客户端发送的信息， 最后将接收到的信息再发送回客户端 。

源码 

头文件（TCPServerTest.h）

#include <iostream>
#include <winsock2.h>
#include <ws2tcpip.h>#include <thread>
#include <functional> // 添加这个头文件以使用 std::bind#include <string>#pragma comment(lib, "ws2_32.lib")class TCPSever {
public:TCPSever(int port);~TCPSever();int createSocket();  //创建套接字int serverPreparation();  //服务器连接准备int startConnectClient();  //接受连接客户端void handleClient(SOCKET clientSocket);  //处理客户端int Port;WSADATA wsaData;SOCKET serverSocket;struct sockaddr_in serverAddr, clientAddr;int addrLen = sizeof(clientAddr);
};

 源文件（TCPServerTest.cpp）

#include "TCPServerTest.h"TCPSever::TCPSever(int port):Port(port)
{// 初始化 Windows Sockets，传入的参数MAKEWORD(2, 2)指定使用 Winsock 2.2 版本，  成功返回0，失败返回非0的错误值if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {  //std::cerr << "Error initializing Winsock\n";}else{createSocket();serverPreparation();startConnectClient();}
}TCPSever::~TCPSever()
{closesocket(this->serverSocket);  // 关闭与服务端的连接，关闭服务端套接字WSACleanup();  //清理 Winsock 库资源
}int TCPSever::createSocket()
{// 创建套接字this->serverSocket = socket(AF_INET, SOCK_STREAM, 0);if (this->serverSocket == INVALID_SOCKET) {std::cerr << "Error creating socket\n";WSACleanup();return 1;}
}int TCPSever::serverPreparation()
{// 设置服务器地址信息this->serverAddr.sin_family = AF_INET;this->serverAddr.sin_addr.s_addr = INADDR_ANY;this->serverAddr.sin_port = htons(Port);// bind 函数 可以绑定套接字到指定地址和端口if (bind(this->serverSocket, (struct sockaddr*)&serverAddr, sizeof(serverAddr)) == SOCKET_ERROR) {std::cerr << "Error binding socket\n";closesocket(this->serverSocket);WSACleanup();return 1;}// listen函数：开始监听连接，参数10表示等待连接队列的最大长度为 10if (listen(this->serverSocket, 10) == SOCKET_ERROR) {std::cerr << "Error listening for connections\n";closesocket(this->serverSocket);WSACleanup();return 1;}std::cout << "Server listening on port " << Port << std::endl;
}int TCPSever::startConnectClient()
{while (true)  //循环接收数据{SOCKET newClientSocket;// 接受客户端连接  accept函数：在循环中等待客户端连接，一旦有客户端连接，会返回一个新的套接字用于与该客户端通信，并获取客户端的地址信息newClientSocket = accept(this->serverSocket, (struct sockaddr*)&clientAddr, &addrLen);if (newClientSocket == INVALID_SOCKET) {std::cerr << "Error accepting connection\n";continue;}char clientIP[INET_ADDRSTRLEN];if (inet_ntop(AF_INET, &clientAddr.sin_addr, clientIP, INET_ADDRSTRLEN) == nullptr) {std::cerr << "Error converting client IP address\n";}else {std::cout << "Client: " << std::string(clientIP)+ ":" + std::to_string(ntohs(clientAddr.sin_port)) << std::endl;std::thread clientThread(std::bind(&TCPSever::handleClient, this, newClientSocket));  //连上后和客户端进行数据clientThread.detach();}}
}void TCPSever::handleClient(SOCKET clientSocket)
{const char* welcomeMessage = "Welcome to the server!\n";send(clientSocket, welcomeMessage, strlen(welcomeMessage), 0);  // 向客户端发送信息char buffer[1024];while (true){int bytesRead = recv(clientSocket, buffer, sizeof(buffer) - 1, 0);if (bytesRead > 0) {buffer[bytesRead] = '\0';std::cout << "Received: " << buffer << std::endl;std::string response = "received: " + std::string(buffer);send(clientSocket, response.c_str(), response.length(), 0);}else {std::cerr << "Connection closed by client\n";closesocket(clientSocket);return;}}
}

调用：

#include "TCPServerTest.h"int main() {TCPSever server = TCPSever(8888);
}

结果

可以看到服务端可以支持多个客户端连接 

客户端代码见：

【C++】创建TCP客户端-CSDN博客