c++ Windows Socket实现最简单的C/S网络通信（TCP）

1.服务器端代码：

#include<iostream>
#include<WinSock2.h>
#pragma comment(lib, "ws2_32.lib")
#define CONNECT_NUM_MAX 10

using namespace std;

int main()
{
	//加载套接字库
	WSADATA wsaData;
	int iRet = 0;
	iRet = WSAStartup(MAKEWORD(2, 2), &wsaData);
	if (iRet != 0)
	{
		cout << "WSAStartup(MAKEWORD(2, 2), &wsaData) execute failed!" << endl;;
		return -1;
	}
	if (2 != LOBYTE(wsaData.wVersion) || 2 != HIBYTE(wsaData.wVersion))
	{
		WSACleanup();
		cout << "WSADATA version is not correct!" << endl;
		return -1;
	}

	//创建套接字
	SOCKET serverSocket = socket(AF_INET, SOCK_STREAM, 0);
	if (serverSocket == INVALID_SOCKET)
	{
		cout << "serverSocket = socket(AF_INET, SOCK_STREAM, 0) execute failed!" << endl;
		return -1;
	}

	//初始化服务器地址族变量
	SOCKADDR_IN addrSrv;
	addrSrv.sin_addr.S_un.S_addr = htonl(INADDR_ANY);
	addrSrv.sin_family = AF_INET;
	addrSrv.sin_port = htons(6000);

	//绑定
	iRet = bind(serverSocket, (SOCKADDR*)&addrSrv, sizeof(SOCKADDR));
	if (iRet == SOCKET_ERROR)
	{
		cout << "bind(serverSocket, (SOCKADDR*)&addrSrv, sizeof(SOCKADDR)) execute failed!" << endl;
		return -1;
	}

	//监听
	iRet = listen(serverSocket, CONNECT_NUM_MAX);
	if (iRet == SOCKET_ERROR)
	{
		cout << "listen(serverSocket, 10) execute failed!" << endl;
		return -1;
	}

	//等待连接_接收_发送
	SOCKADDR_IN clientAddr;
	int len = sizeof(SOCKADDR);
	while (1)
	{
		SOCKET connSocket = accept(serverSocket, (SOCKADDR*)&clientAddr, &len);
		if (connSocket == INVALID_SOCKET)
		{
			cout << "accept(serverSocket, (SOCKADDR*)&clientAddr, &len) execute failed!" << endl;
			return -1;
		}

		char sendBuf[100];
		sprintf_s(sendBuf, "Welcome %s", inet_ntoa(clientAddr.sin_addr));
		send(connSocket, sendBuf, strlen(sendBuf)+1, 0);

		char recvBuf[100];
		recv(connSocket, recvBuf, 100, 0);
		printf("%s\n", recvBuf);
		closesocket(connSocket);
	}

	system("pause");
	return 0;
}

2.客户端代码：

#include<iostream>
#include <winsock2.h>
using namespace std;

#pragma comment(lib, "ws2_32.lib")
int main()
{
	//加载套接字库
	WSADATA wsaData;
	int iRet =0;
	iRet = WSAStartup(MAKEWORD(2, 2), &wsaData);
	if (iRet != 0)
	{
		cout << "WSAStartup(MAKEWORD(2, 2), &wsaData) execute failed!" << endl;
		return -1;
	}
	if (2 != LOBYTE(wsaData.wVersion) || 2 != HIBYTE(wsaData.wVersion))
	{
		WSACleanup();
		cout << "WSADATA version is not correct!" << endl;
		return -1;
	}

	//创建套接字
	SOCKET clientSocket = socket(AF_INET, SOCK_STREAM, 0);
	if (clientSocket == INVALID_SOCKET)
	{
		cout << "clientSocket = socket(AF_INET, SOCK_STREAM, 0) execute failed!" << endl;
		return -1;
	}

	//初始化服务器端地址族变量
	SOCKADDR_IN srvAddr;
	srvAddr.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");
	srvAddr.sin_family = AF_INET;
	srvAddr.sin_port = htons(6000);

	//连接服务器
	iRet = connect(clientSocket, (SOCKADDR*)&srvAddr, sizeof(SOCKADDR));
	if (0 != iRet)
	{
		cout << "connect(clientSocket, (SOCKADDR*)&srvAddr, sizeof(SOCKADDR)) execute failed!" << endl;
		return -1;
	}

	//接收消息
	char recvBuf[100];
	recv(clientSocket, recvBuf, 100, 0);
	printf("%s\n", recvBuf);

	//发送消息
	char sendBuf[100];
	sprintf_s(sendBuf, "Hello, This is client %s", "兔子");
	send(clientSocket, sendBuf, strlen(sendBuf)+1, 0);

	//清理
	closesocket(clientSocket);
	WSACleanup();

	system("pause");
	return 0;
}

3.程序运行截图：