用UDP实现客户端与服务器的连接

#include <winsock2.h> #include <stdio.h> #pragma comment(lib, "WS2_32") // 链接到WS2_32.lib BOOL InitWinsock(); void main() { SOCKET socket1; InitWinsock(); struct sockaddr_in local; struct sockaddr_in from; int fromlen =sizeof(from); local.sin_family=AF_INET; local.sin_port=htons(1000); ///监听端口 local.sin_addr.s_addr=INADDR_ANY; ///本机 socket1=socket(AF_INET,SOCK_DGRAM,0); bind(socket1,(struct sockaddr*)&local,sizeof local); while (1) { char buffer[1024]="\0"; printf("waiting for message from others-------------\n"); if (recvfrom(socket1,buffer,sizeof buffer,0,(struct sockaddr*)&from,&fromlen)!=SOCKET_ERROR) { printf("Received datagram from %s--%s\n",inet_ntoa(from.sin_addr),buffer); ////给cilent发信息 sendto(socket1,buffer,sizeof buffer,0,(struct sockaddr*)&from,fromlen); } Sleep(500); } closesocket(socket1); } BOOL InitWinsock() { int Error; WORD VersionRequested; WSADATA WsaData; VersionRequested=MAKEWORD(2,2); Error=WSAStartup(VersionRequested,&WsaData); //启动WinSock2 if(Error!=0) { return FALSE; } else { if(LOBYTE(WsaData.wVersion)!=2||HIBYTE(WsaData.wHighVersion)!=2) { WSACleanup(); return FALSE; } } return TRUE; }