VC++ TCP网络控制台程序

     在Windows7系统下，采用工具为VS2008，Win32控制台应用程序，编写一个基于TCP的Client/Server网络程序。

1、服务器端代码

#include <WinSock2.h>
#include <stdio.h>

#define SERVERPORT 6000	//服务端口号

int main(int argc, char *argv[])
{
	//加载套接字库
	WORD wVersionRequested;//用于保存WinSock库的版本号
	WSADATA wsaData;
	int err;
	
	printf("This is a Server side application!
");

	wVersionRequested = MAKEWORD(2,2);

	err = WSAStartup( wVersionRequested, &wsaData);
	if (err != 0)
	{
		printf("WSAStartup() called failed!
");
		return -1;
	}
	else
	{
		printf("WSAStartup() called successful!
");
	}

	if (LOBYTE(wsaData.wVersion) != 2 ||
		  HIBYTE(wsaData.wVersion) != 2)
	{
		//若不是所请求的版本号2.2，则终止WinSock库的使用
		WSACleanup();
		return -1;
	}

	//创建用于监听的套接字
	SOCKET sockServer = socket(AF_INET, SOCK_STREAM, 0);
	if(sockServer == INVALID_SOCKET)
	{
		printf("socket() called failed! ,error code is: %d", WSAGetLastError());
		return -1;
	}
	else
	{
		printf("socket() called successful!
");
	}
	
	//填充服务器端套接字结构
	SOCKADDR_IN addrServer;
	addrServer.sin_addr.S_un.S_addr = htonl(INADDR_ANY);//将主机字节顺序转换成TCP/IP网络字节顺序
	addrServer.sin_family = AF_INET;
	addrServer.sin_port = htons(SERVERPORT);

	//将套接字绑定到一个本地地址和端口上
	err = bind(sockServer, (SOCKADDR*)&addrServer, sizeof(SOCKADDR));
	if (err == SOCKET_ERROR)
	{
		printf("bind() called failed! The error code is: %d
", WSAGetLastError());
		return -1;
	}
	else
	{
		printf("bind() called successful
");
	}
	//将套接字设置为监听模式，准备接收客户请求
	err = listen(sockServer, 5);
	if (err == SOCKET_ERROR)
	{
		printf("listen() called failed! The error code is: %d
", WSAGetLastError());
		return -1;
	}
	else
	{
		printf("listen() called successful!
");
	}

	SOCKADDR_IN addrClient;	//保存发送请求连接的客户端的套接字信息
	int len = sizeof(SOCKADDR);
	
	while(1)
	{
		//等待客户请求到来
		SOCKET sockConn = accept(sockServer, (SOCKADDR*)&addrClient, &len);
		if (sockConn == INVALID_SOCKET)
		{
			printf("accept() called falied! The error code is: %d
", WSAGetLastError());
		}
		else
		{
			printf("The Server receive a new client connection!
");
		}

		char sendBuf[100];
		sprintf_s(sendBuf, 100, "Welcome %s",inet_ntoa(addrClient.sin_addr));

		//发送数据
		send(sockConn, sendBuf, strlen(sendBuf)+1 , 0);
		char recvBuf[100];
		//接收数据
		recv(sockConn, recvBuf, 100, 0);
		//打印接收到的数据
		printf("receive data from client side [%s,%d] is: %s
", inet_ntoa(addrClient.sin_addr), addrClient.sin_port,
			                  recvBuf);
		closesocket(sockConn);	//关闭连接套接字
	}

	return 0;
}

2、客户端代码

#include <WinSock2.h>
#include <stdio.h>

#define SERVERPORT 6000	//服务端口号

#pragma comment(lib, "WS2_32.lib");

int main(int argc, char *argv[])
{
	//加载套接字库
	WORD wVersionRequested;
	WSAData wsaData;
	int err;

	printf("This is a Client side application!
");

	wVersionRequested = MAKEWORD( 2, 2 );

	err = WSAStartup(wVersionRequested, &wsaData);
	if (err != 0 )
	{
		/* Tell the user that we could not find a usable */
		/* WinSock DLL.                                  */
		printf("WSAStartup() called failed!
");
		return -1;
	}
	else
	{
		printf("WSAStartup() called successful!
");
	}

	if ( LOBYTE( wsaData.wVersion ) != 2 ||
		HIBYTE( wsaData.wVersion ) != 2 ) {
			/* Tell the user that we could not find a usable */
			/* WinSock DLL.                                  */
			WSACleanup( );
			return -1; 
	}

	/* The WinSock DLL is acceptable. Proceed. */
	
	//创建套接字
	SOCKET sockClient = socket(AF_INET, SOCK_STREAM, 0);
	if(sockClient == INVALID_SOCKET)
	{
		printf("socket() called failed! ,error code is: %d", WSAGetLastError());
		return -1;
	}
	else
	{
		printf("socket() called successful!
");
	}
	
	//需要连接的服务端套接字结构信息
	SOCKADDR_IN addrServer;
	addrServer.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");//设定服务器的IP地址
	addrServer.sin_family = AF_INET;
	addrServer.sin_port = htons(SERVERPORT);//设定服务器的端口号(使用网络字节序)
      
	//向服务器发出连接请求
	err = connect(sockClient, (SOCKADDR*)&addrServer, sizeof(SOCKADDR));
	if (err == SOCKET_ERROR)
	{
		printf("connect() called failed! The error code is: %d
", WSAGetLastError());
		return -1;
	}
	else
	{
		printf("connect() called successful
");
	}

	//接收数据
	char recvBuf[100]={0};
	recv(sockClient, recvBuf, 100, 0);
	printf("receive data from server side is: %s
", recvBuf);
                                       
	//发送数据
	send(sockClient, "This is a client side!
", strlen("This is a client side!
")+1, 0);

	//关闭套接字
	closesocket(sockClient);
	
	//终止套接字库的使用
	WSACleanup();

	return 0;
}

另外，需要注意的是需要在服务器和客户端都需要链接WinSock静态链接库Ws2_32.lib，有两种添加方法

方法一：在工程配置属性中添加

假如创建一个名为TCPClient的Win32控制台应用程序

在VC2008中添加静态链接库WS2_32.lib的方法如下：

(1)切换到TCPServer的【Solution Explorer】，选择菜单【Project】->【TCPClient Properties】

(2)在TCPClient Properties Pages对话框中，依次选择【Configuration Properties】->【Linker】->【Input】，在右侧的【Addtional Dependencies】中添加Ws2_32.lib库。

如下如所示：

服务器TCPServer也需要链接Ws2_32.lib库,方法和客户端TCPClient一样。

程序结果运行如下：

先启动服务器端程序TCPServer，结果如下：

再启动客户端TCPClient，客户端结果如下：

服务器端TCPServer结果如下：

方法二：在代码中添加

#pragma comment(lib, "WS2_32.lib");

参考资料：

1、《VC++深入详解》 第14章网络编程 ，孙鑫主编

2、MSDN帮助文档