转自 http://hereson.javaeye.com/blog/198771

下面是一个C++调用windows API实现有通信程序,您可以据此进行修改,封装成类.

// *******************************************************************

// client.cpp : Defines the entry point for the console application.
// *******************************************************************

#include "stdafx.h"
#include <winsock2.h>
#include <iostream>
#define PORT_SERVER 6656

int main(int argc, char* argv[])
{
std::cout << "Start up tcp client." << std::endl;

WSADATA wsaData;
WORD sockVersion = MAKEWORD(2, 0);
if (0 != WSAStartup(sockVersion, &wsaData))
{
   std::cout << "Failed to retrive socket version."
    << std::endl;
   return 0;
}

SOCKET sock_client;
sock_client = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if (INVALID_SOCKET == sock_client)
{
   std::cout << "Invalid socket." << std::endl;
   WSACleanup();
   return 0;
}
sockaddr_in addr_sev;
addr_sev.sin_family = AF_INET;
addr_sev.sin_port = htons(PORT_SERVER);
addr_sev.sin_addr.s_addr = inet_addr("127.0.0.1");
if (SOCKET_ERROR == connect(sock_client, (sockaddr *)&addr_sev, sizeof(addr_sev)))
{
   std::cout << "Failed to connect." << std::endl;
   WSACleanup();
   return 0;
}

char buf[512];
int recv_size = 0;
recv_size = recv(sock_client, buf, 512, 0);
if (512 > recv_size)
{
   buf[recv_size] = '/0';
   std::cout << "receive data is :" << buf << std::endl;
   memset(buf, 0, sizeof(buf));
}
else
{
   std::cout << "receive data is overflow" << std::endl;
}

closesocket(sock_client);
WSACleanup();
system("PAUSE");
return 0;
}

// *******************************************************************

// server.cpp : Defines the entry point for the console application.

#include "stdafx.h"
#include <winsock2.h>
#include <iostream>
#define PORT_SERVER 6656
#define NUM_CLIENTS 10

int main(int argc, char* argv[])
{
std::cout << "Start up tcp server." << std::endl;

WSADATA wsaData;
WORD sockVersion = MAKEWORD(2, 0);
if (0 != WSAStartup(sockVersion, &wsaData))
{
   std::cout << "Failed to retrive socket version."
         << std::endl;
   return 0;
}

SOCKET sock_sev;
sock_sev = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if (INVALID_SOCKET == sock_sev)
{
   std::cout << "Invalid socket." << std::endl;
   WSACleanup();
   return 0;
}

sockaddr_in addr_sev;
addr_sev.sin_family = AF_INET;
addr_sev.sin_port = htons(PORT_SERVER);
addr_sev.sin_addr.s_addr = INADDR_ANY;
if (SOCKET_ERROR == bind(sock_sev, (sockaddr *)&addr_sev, sizeof(addr_sev)))
{
   std::cout << "Failed to bind." << std::endl;
   WSACleanup();
   return 0;
}
if (SOCKET_ERROR == listen(sock_sev, NUM_CLIENTS))
{
   std::cout << "Failed to listen." << std::endl;
   WSACleanup();
   return 0;
}

// 多路复用,暂时还未实现.后期会对此给出示例.
//fd_set reads;
//fd_set writes;
//fd_set accepts;
//FD_ZERO(&reads);
//FD_ZERO(&writes);
//FD_ZERO(&accepts);
//SOCKET sock_client;
sockaddr_in addr_client;
int nAddrLen = sizeof(addr_client);
while (true)
{
   char tmp[512];
   sock_client = accept(sock_sev, (sockaddr *)&addr_client, &nAddrLen);
  
   if (INVALID_SOCKET == sock_client)
   {
    std::cout << "Failed to accept." << std::endl;
    continue;
   }
   sprintf(tmp, "Your IP is %s/n", inet_ntoa(addr_client.sin_addr));
   send(sock_client, tmp, strlen(tmp), 0);
   std::cout << "Connection from " << inet_ntoa(addr_client.sin_addr)
         << std::endl;

   closesocket(sock_client);
}

return 0;
}

注:本程序使用的是VC6 IDE,编译时请在link中加入对ws2_32.lib库的引用.