TCP SOCKET服务器|客户端简单实现

// Windows_TCP_socket_Sever.cpp : 定义控制台应用程序的入口点。//#include "stdafx.h"#include<iostream>#include<WINSOCK2.H>#pragma comment (lib,"Ws2_32.lib")using namespace std;int _tmain(int argc, _TCHAR* argv[]){//初始化Ws2_32.libWSADATA data;if(WSAStartup(MAKEWORD(2,2),&data)!=0){cout<<"WSAStartup无法初始化"<<endl;return 0;}//cout<<"version:"<<LOBYTE(data.wVersion)<<"."<<HIBYTE(data.wVersion)<<endl;printf("version:%d.%d\n",LOBYTE(data.wVersion),HIBYTE(data.wVersion));//c++输出10进制？//cout<<"High Version:"<<dec<<LOBYTE(data.wHighVersion)<<"."<<HIBYTE(data.wHighVersion)<<endl;printf("version:%d.%d\n",LOBYTE(data.wHighVersion),HIBYTE(data.wHighVersion));cout<<"Description:"<<data.szDescription<<endl;cout<<"System Status:"<<data.szSystemStatus<<endl;//创建监听套接字SOCKET ListenSocket;ListenSocket=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);if(ListenSocket==INVALID_SOCKET){cout<<"Socket error!"<<endl;WSACleanup();return -1;}//创建套接字地址结构，绑定SOCKADDR_IN Saddr;Saddr.sin_family=AF_INET;Saddr.sin_port=htons(1020);Saddr.sin_addr.s_addr=htons(INADDR_ANY);//sin_addr是IP地址结构体in_addr的结构对象，s_addr是sin_addr的结构成员，存放32位IP地址int errcode=bind(ListenSocket,(sockaddr*)&Saddr,sizeof(SOCKADDR_IN));//(sockaddr*)&saClient强制类型转化，从sockaddr_in类型转换成sockaddr类型。winsock API中使用sockaddr类，程序中使用sockaddr_in类if(errcode==SOCKET_ERROR){cout<<"bind failed!"<<endl;closesocket(ListenSocket);WSACleanup();return -1;}//在套接字上监听int value=listen(ListenSocket,5);if(value==SOCKET_ERROR){cout<<"listen error!"<<endl;closesocket(ListenSocket);WSACleanup();return -1;}cout<<"TCP Server start...\r"<<endl;//创建客户端套接字与地址结构SOCKET ClientSocket;SOCKADDR_IN Clientaddr;int len=sizeof(Clientaddr);ClientSocket=accept(ListenSocket,(sockaddr FAR*)&Clientaddr,&len);//1.监听套接字 2.新的地址结构对象存放客户端套接字地址 3.客户端对象长度if(ClientSocket!=INVALID_SOCKET){//accept成功，返回一个新的套接字句柄，否则返回>>>INVALID_SOCKET<<<.WSAGetLastError函数可以获取错误代码,第一个参数是监听套接字cout<<inet_ntoa(Clientaddr.sin_addr)<<"已经连接上\r\n"<<endl;}elsecout<<"accept:"<<WSAGetLastError()<<endl;char sendbuf[]="hello,you have already connected.\r";send(ClientSocket,sendbuf,sizeof(sendbuf),0);//SO_MAX_MSG_SIZE可以用来获取系统允许的最大字符串长度while(true){char recvbuf[100];errcode=recv(ClientSocket,recvbuf,100,0);if(errcode==0)cout<<"The connection has closed.\n";else if(errcode==SOCKET_ERROR)cout<<WSAGetLastError()<<endl;else{cout<<"Client said:  "<<recvbuf<<endl;if(strcmp(recvbuf,"quit")==0)break;}}//关闭套接字，释放资源closesocket(ClientSocket);closesocket(ListenSocket);if(WSACleanup()==SOCKET_ERROR)cout<<"WSACleanup error!"<<endl;if(getchar())return 0;}

TCP服务器端实现步骤：

1.建立监听套接字，返回套接字句柄

2.建立本地套接字地址结构，与套接字绑定bind（）

3.监听套接字监听端口listen（）

4.等待客户端连接请求accept（）,建立连接，得到连接套接字

5.在套接字上读写数据send（），recv（）等

6.关闭连接套接字与监听套接字

// Windows_TCP_client.cpp : 定义控制台应用程序的入口点。//#include "stdafx.h"#include<iostream>#include<WINSOCK2.H>#pragma comment (lib,"Ws2_32.lib")using namespace std;#define BUF_SIZE 64int _tmain(int argc, _TCHAR* argv[]){WSADATA wsd;SOCKET client;if(WSAStartup(MAKEWORD(2,2),&wsd)!=0)//执行成功返回0{cout<<"WSAStartup failed!\n";//return -1;}/*************************************************************************************** *client=(AF_INET,SOCK_STREAM,IPPROTO_TCP);  少了socket函数名，所以运行出现问题 * ***************************************************************************************/client=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);//设置服务器地址SOCKADDR_IN saddr;saddr.sin_family=AF_INET;saddr.sin_port=htons(1020);saddr.sin_addr.S_un.S_addr=inet_addr("127.0.0.1");int len=sizeof(saddr);//连接服务器int value=connect(client,(sockaddr*)&saddr,len);if(value==INVALID_SOCKET){cout<<"connect failed!"<<endl;closesocket(client);WSACleanup();return -1;}char recvbuf[BUF_SIZE];value=recv(client,recvbuf,BUF_SIZE,0);cout<<"Server:"<<recvbuf<<endl;while(true){cout<<"please input a string to send:\n";char sendbuf[BUF_SIZE];cin>>sendbuf;int value=send(client,sendbuf,BUF_SIZE,0);if(value==SOCKET_ERROR){cout<<"send failed!"<<endl;closesocket(client);WSACleanup();//return -1;}}closesocket(client);WSACleanup();if(getchar())return 0;}

TCP客户端实现

1.建立连接套接字，返回句柄

2.将套接字与远程主机相连connect（）

3.与客户端通信recv（），send（）

4.关闭套接字