1、要求：

服务端从客户端获取多个数字和运算符信息，服务端收到数字后对其进行加减乘运算，然后把结果传给客户端。

2、客户端实现：client.cpp

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <WinSock2.h>#define BUF_SIZE 1024
#define RLT_SIZE 4
#define OPSZ 4void ErrorHandling(char *message);int main(int argc,char *argv[])
{WSADATA wsadata;SOCKET hsocket;char opmsg[BUF_SIZE];int result,opndCnt,i;SOCKADDR_IN servAdr;if (argc!=3){printf("usage:%s <ip> <port>\n",argv[0]);exit(1);}//初始化套接字库,主版本2，副版本2if (WSAStartup(MAKEWORD(2,2),&wsadata)!=0)ErrorHandling("WSAStartup() error");//创建套接字hsocket = socket(PF_INET,SOCK_STREAM,0);//判断套接字是否有效if (hsocket==INVALID_SOCKET)ErrorHandling("socket() error");//初始化地址信息memset(&servAdr,0,sizeof(servAdr));servAdr.sin_family = AF_INET;//指定地址族servAdr.sin_addr.s_addr = inet_addr(argv[1]);//servAdr.sin_port = htons(atoi(argv[2]));//把short数据从主机字节序转化为网络字节序 作为地址端口号//客户端向服务器发送连接请求if(connect(hsocket,(SOCKADDR*)&servAdr,sizeof(servAdr))==SOCKET_ERROR)ErrorHandling("connect() error");elseputs("connected...");fputs("operand count: ",stdout);//输入运算数个数scanf("%d",&opndCnt);opmsg[0] = (char)opndCnt;//输入运算数for (i=0;i<opndCnt;i++){printf("operand count:",i+1);scanf("%d",(int*)&opmsg[i*OPSZ+1]);}fgetc(stdin);fputs("operator: ",stdout);scanf("%c",&opmsg[opndCnt*OPSZ+1]);//数据传输send(hsocket,opmsg,opndCnt*OPSZ+2,0);//-----接收服务器发来的消息----------recv(hsocket,(char*)&result,RLT_SIZE,0);//输出运算结果printf("operation result: %d\n",result);//关闭套接字closesocket(hsocket);//注销套接字库WSACleanup();return 0;
}//错误处理函数
void ErrorHandling(char *message)
{fputs(message,stderr);fputc('\n',stderr);exit(1);
}

3、服务端实现：server.cpp

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <WinSock2.h>#define BUF_SIZE 1024
#define OPSZ 4void ErrorHandling(char *message);
int calculate(int opnum,int opnds[],char operater);int main(int argc,char *argv[]){WSADATA wsadata;SOCKET hServSock,hClntSock;char opinfo[BUF_SIZE];int result,opndCnt,i;int recvCnt, recvLen;SOCKADDR_IN servAdr,clntAdr;int clntAdrSize;if (argc!=2){printf("usage: %s <port>\n",argv[0]);exit(1);}if(WSAStartup(MAKEWORD(2,2,),&wsadata)!=0)ErrorHandling("WSAStartup error");hServSock = socket(PF_INET,SOCK_STREAM,0);if (hServSock == INVALID_SOCKET)ErrorHandling("socket() error");memset(&servAdr,0,sizeof(servAdr));servAdr.sin_family = AF_INET;servAdr.sin_addr.s_addr = htonl(INADDR_ANY);servAdr.sin_port = htons(atoi(argv[1]));if (bind(hServSock,(SOCKADDR*)&servAdr,sizeof(servAdr))==SOCKET_ERROR)ErrorHandling("bind() error");if (listen(hServSock,5)==SOCKET_ERROR)ErrorHandling("listen() error");clntAdrSize = sizeof(clntAdr);for (i=0;i<5;i++){opndCnt = 0;hClntSock = accept(hServSock,(SOCKADDR*)&clntAdr,&clntAdrSize);recv(hClntSock,(char*)&opndCnt,1,0);recvLen = 0;while (opndCnt*OPSZ+1>recvLen){recvCnt = recv(hClntSock,&opinfo[recvLen],BUF_SIZE-1,0);recvLen += recvCnt;}result = calculate(opndCnt,(int*)opinfo,opinfo[recvLen-1]);send(hClntSock,(char*)&result,sizeof(result),0);closesocket(hClntSock);}closesocket(hServSock);WSACleanup();return 0;
}int calculate(int opnum,int opnds[],char op){int res = opnds[0],i;switch(op){case '+':for (i=1;i<opnum;i++)res += opnds[i];break;case '-':for (i=1;i<opnum;i++)res -= opnds[i];break;case '*':for (i=1;i<opnum;i++)res *= opnds[i];break;}return res;
}//错误处理函数
void ErrorHandling(char *message)
{fputs(message,stderr);fputc('\n',stderr);exit(1);
}