
服务端:
// WSASever.cpp : 定义控制台应用程序的入口点。
//
#include "stdafx.h"
#include <WinSock2.h>
#include <Windows.h>
#pragma comment (lib,"wSock32.lib")
int _tmain(int argc, _TCHAR* argv[])
{
    WORD wVersionRequested;
    WSADATA wsaData;
    int err;
    wVersionRequested = MAKEWORD(2, 2);
    err = WSAStartup(wVersionRequested, &wsaData);
    if (err != 0) {
        printf("WSAStartup failed with error: %d\n", err);
        return 1;
    }
    if (LOBYTE(wsaData.wVersion) != 2 || HIBYTE(wsaData.wVersion) != 2)
    {
        printf("Could not find a usable version of Winsock.dll\n");
        WSACleanup();
        return 1;
    }
    else
        printf("The Winsock 2.2 dll was found okay\n");
    //程序开始
    
    //创建socket->bing-》listen->accept->recv->send->closesocket
    SOCKET severSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (severSocket == INVALID_SOCKET)
    {
        printf("new socket error!");
    }
    SOCKADDR_IN sockAddr;
    sockAddr.sin_port = htons(10086);
    sockAddr.sin_family = AF_INET;
    //IP地址表示方法
    /*方法1:  m_addr.sin_addr.S_un.S_un_b.s_b1 = 192; m_addr.sin_addr.S_un.S_un_b.s_b2 = 168; m_addr.sin_addr.S_un.S_un_b.s_b3 = 0; m_addr.sin_addr.S_un.S_un_b.s_b4 = 1;
    方法2:  m_addr.sin_addr.S_un.S_un_w.s_w1 = (168 << 8) | 192; m_addr.sin_addr.S_un.S_un_w.s_w2 = (1 << 8) | 0;
    方法3:  m_addr.sin_addr.S_un.S_addr = (1 << 24) | (0 << 16) | (168 << 8) | 192
    方法4;    service.sin_addr.s_addr = inet_addr("127.0.0.1");
    */
    //sockAddr.sin_addr.s_addr = inet_addr(INADDR_ANY);
    sockAddr.sin_addr.S_un.S_un_b.s_b1 = 127;
    sockAddr.sin_addr.S_un.S_un_b.s_b2 = 0;
    sockAddr.sin_addr.S_un.S_un_b.s_b3 = 0;
    sockAddr.sin_addr.S_un.S_un_b.s_b4 = 1;
    if (bind(severSocket, (sockaddr*)&sockAddr, sizeof(SOCKADDR_IN)) == SOCKET_ERROR)
    {
        printf("bind error! %d\n", WSAGetLastError());
    }
    //监听1个
    if (listen(severSocket, 5) == SOCKET_ERROR)
    {
        printf("listen error!%d\n", WSAGetLastError());
    }
    //创建一个一客户端连接的socket
    SOCKET sockLink = accept(severSocket, NULL, NULL);
    if (sockLink != INVALID_SOCKET)
    {
        printf("communication sucess!\n");
    }
    int nErr=0;
    while (true)
    {
        char pSeverBuff[MAXBYTE] = { 0 };
        nErr = recv(sockLink, pSeverBuff, MAXBYTE, 0);
        printf("%s(%d)%s\n", inet_ntoa(sockAddr.sin_addr), sockAddr.sin_port, pSeverBuff);
        send(sockLink, pSeverBuff, MAXBYTE, 0);
        //当客户端关闭时,服务端也随之关闭
        if (nErr == INVALID_SOCKET)
            break;
    }
    closesocket(severSocket);
    closesocket(sockLink);
    WSACleanup();
    return 0;
}
 
 
客户端
// WASClient.cpp : 定义控制台应用程序的入口点。
//
//#include <WinSock2.h>一定要在#include <Windows.h>前面
#include "stdafx.h"
#include <WinSock2.h>
#include <Windows.h>
#pragma comment (lib,"wSock32.lib")
int _tmain(int argc, _TCHAR* argv[])
{
    WORD wVersionRequested;
    WSADATA wsaData;
    int err;
    
    //版本检测
    wVersionRequested = MAKEWORD(2, 2);
    err = WSAStartup(wVersionRequested, &wsaData);
    if (err != 0) {
        printf("WSAStartup failed with error: %d\n", err);
        return 1;
    }
    if (LOBYTE(wsaData.wVersion) != 2 || HIBYTE(wsaData.wVersion) != 2) 
    {
        printf("Could not find a usable version of Winsock.dll\n");
        WSACleanup();
        return 1;
    }
    else
        printf("The Winsock 2.2 dll was found okay\n");
    //程序开始
    //创建socket-》连接connect-》发送send-》接受recv-》释放closesocke
    SOCKET clientSocket=socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (clientSocket == INVALID_SOCKET)
    {
        printf("new socket error!");
    }
    SOCKADDR_IN sockAddr;
    //一定要把主机字节序换成网络字节序 并是short类型   htons()
    sockAddr.sin_port = htons(10086);
    sockAddr.sin_family = AF_INET;
    //IP地址表示方法
    /*方法1:  m_addr.sin_addr.S_un.S_un_b.s_b1 = 192; m_addr.sin_addr.S_un.S_un_b.s_b2 = 168; m_addr.sin_addr.S_un.S_un_b.s_b3 = 0; m_addr.sin_addr.S_un.S_un_b.s_b4 = 1; 
    方法2:  m_addr.sin_addr.S_un.S_un_w.s_w1 = (168 << 8) | 192; m_addr.sin_addr.S_un.S_un_w.s_w2 = (1 << 8) | 0; 
    方法3:  m_addr.sin_addr.S_un.S_addr = (1 << 24) | (0 << 16) | (168 << 8) | 192*/
    sockAddr.sin_addr.S_un.S_un_b.s_b1 = 127;
    sockAddr.sin_addr.S_un.S_un_b.s_b2 = 0;
    sockAddr.sin_addr.S_un.S_un_b.s_b3 = 0;
    sockAddr.sin_addr.S_un.S_un_b.s_b4 = 1;
    if (connect(clientSocket, (sockaddr*)&sockAddr, sizeof(SOCKADDR_IN)) != SOCKET_ERROR)
    {
        printf("communication sucess!\n");
    }
    char pClientBuf[MAXBYTE] = {0};
    //请求连接
    while (TRUE)
    {
        gets_s(pClientBuf);
        send(clientSocket, pClientBuf, MAXBYTE, 0);
        
        recv(clientSocket, pClientBuf, MAXBYTE, 0);
        printf("return from sever:%s\n", pClientBuf);
    }
    WSACleanup();
    closesocket(clientSocket);
    return 0;
}