開發環境：

window7

VisualStudio2015

服務端代碼：server.cpp

#include <stdio.h>#include <winsock2.h>#PRagma comment (lib, "ws2_32.lib")  //加載 ws2_32.dll#include <iostream>using namespace std;//線程#include <cstdlib>#include <windows.h>//聲明DWord WINAPI Fun1Proc(LPVOID lpParameter);int main(){	printf("start server/n");	/*** 可參考文檔 http://c.biancheng.net/cpp/html/3031.html **/	//初始化 DLL	WSADATA wsaData;	WSAStartup(MAKEWORD(2, 2), &wsaData);	//創建套接字	SOCKET servSock = socket(PF_INET, SOCK_STREAM, ipPROTO_TCP);	//綁定套接字	sockaddr_in sockAddr;	memset(&sockAddr, 0, sizeof(sockAddr));  //每個字節都用0填充	sockAddr.sin_family = PF_INET;  //使用IPv4地址	sockAddr.sin_addr.s_addr = inet_addr("127.0.0.1");  //具體的IP地址	sockAddr.sin_port = htons(1234);  //端口	bind(servSock, (SOCKADDR*)&sockAddr, sizeof(SOCKADDR));	//進入監聽狀態	listen(servSock, 20);	//接收客戶端請求	//SOCKADDR clntAddr;	SOCKADDR_IN clntAddr;	int nSize = sizeof(SOCKADDR);	while (true)	{		SOCKET clntSock = accept(servSock, (SOCKADDR*)&clntAddr, &nSize);		//告訴用戶誰上線		char szIpAddress[16];		strcpy_s(szIpAddress, sizeof(szIpAddress), inet_ntoa(clntAddr.sin_addr));		//cout << szIpAddress << "上線了" << endl;		HANDLE hThread_1 = CreateThread(NULL, 0, Fun1Proc, (LPVOID)&clntSock, 0, NULL);		CloseHandle(hThread_1);	}		closesocket(servSock);	//終止 DLL 的使用	WSACleanup();	printf("end server/n");	system("pause");	return 0;}DWORD WINAPI Fun1Proc(LPVOID lpParameter ){	SOCKET clntSock = *(SOCKET*)lpParameter;		//接收服務器傳回的數據	char szBuffer[MAXBYTE] = { 0 };	recv(clntSock, szBuffer, MAXBYTE, NULL);	//輸出接收到的數據	//printf("Message form client: %s/n", szBuffer);	cout << "Message form client: " << szBuffer << endl;	//strcat(szBuffer, "發送出去");	//向客戶端發送數據	char *str = szBuffer;	send(clntSock, str, strlen(str) + sizeof(char), NULL);	//關閉套接字	//closesocket(clntSock);	return 0;}
客戶端代碼：client.cpp
#include <stdio.h>#include <stdlib.h>#include <WinSock2.h>#pragma comment(lib, "ws2_32.lib")  //加載 ws2_32.dll#include <iostream>using namespace std;int main() {	//初始化DLL	WSADATA wsaData;	WSAStartup(MAKEWORD(2, 2), &wsaData);	SOCKET sock = NULL;	while (true)	{		//創建套接字		sock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);		//向服務器發起請求		sockaddr_in sockAddr;		memset(&sockAddr, 0, sizeof(sockAddr));  //每個字節都用0填充		sockAddr.sin_family = PF_INET;		sockAddr.sin_addr.s_addr = inet_addr("127.0.0.1");		sockAddr.sin_port = htons(1234);			connect(sock, (SOCKADDR*)&sockAddr, sizeof(SOCKADDR));		 		cout << "Please input :" ;		char sendString[500];		cin >> sendString ;		 		strcat(sendString, "/n");		//向服務端端發送數據		char *sendStr = sendString;		send(sock, sendStr, strlen(sendStr) + sizeof(char), NULL);		cout << sendString << endl;		//接收服務器傳回的數據		char szBuffer[MAXBYTE] = { 0 };		recv(sock, szBuffer, MAXBYTE, NULL);		//輸出接收到的數據		//	printf("Message form server: %s/n", szBuffer);		cout << "Message form server:" << szBuffer << endl;		//關閉套接字		closesocket(sock);	}		//終止使用 DLL	WSACleanup();	system("pause");	return 0;}
源代碼下載地址：http://download.csdn.net/detail/baidu_19473529/9748318
寫的不好的地方，萬忘指正。