UDP聊天代码（C语言）

#include <stdio.h> #include <winsock2.h>//把程序所需头文件winsock2.h包含进来 #pragma comment(lib,"ws2_32.lib") void main(void) { WSADATA wsaData; SOCKET NewConnection; SOCKADDR_IN ServerAddr; //设置服务器端套接字的相关属性 SOCKADDR_IN ClientAddr; //用来接收客户端的设置，包括IP和端口 int sendlen=sizeof(ClientAddr); int reclen=sizeof(ClientAddr); int ClientAddrLen; int Port = 8080; int Ret; int n =1; char DataBuffer[1024]; //ClientAddrLen = sizeof(ClientAddr); //初始化 winsocket if ((Ret = WSAStartup(MAKEWORD(2,2), &wsaData)) != 0) //版本号为2.2 { printf("WSAStartup 打开错误 %d\n", Ret); WSACleanup(); return; } //建立socket 用于接收数据 if ((NewConnection = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) //与TCP IP设置参数不一样 == INVALID_SOCKET) { printf("socket 创建错误 %d\n", WSAGetLastError()); closesocket(NewConnection); WSACleanup(); return; } //绑定socket ServerAddr.sin_family = AF_INET; ServerAddr.sin_port = htons(Port); //设置端口号 ServerAddr.sin_addr.S_un.S_addr = inet_addr("127.0.0.1"); //设置IP 127.0.0.1 //调用bind()函数 if (bind(NewConnection, (SOCKADDR *)&ServerAddr, sizeof(ServerAddr)) == SOCKET_ERROR) //将套接字绑定到本地地址和指定端口上 { printf("bind 绑定错误 %d\n", WSAGetLastError()); closesocket(NewConnection); WSACleanup(); return; } //设置服务器地址socket ClientAddr.sin_family = AF_INET; ClientAddr.sin_port = htons(8081); //设置端口号 ClientAddr.sin_addr.S_un.S_addr = inet_addr("127.0.0.1"); //设置IP 127.0.0.1 // 服务器接接并发送消息 while(1) //不断监听 { if ((Ret = recvfrom(NewConnection, DataBuffer, sizeof(DataBuffer),0,(SOCKADDR *)&ClientAddr, &sendlen)) //从客户端接收数据，结果显示在服务器上 == SOCKET_ERROR) { printf("接收数据错误 %d\n", WSAGetLastError()); closesocket(NewConnection); WSACleanup(); return; } DataBuffer[Ret]='\0'; printf("刘如通说的第%d句话: %s\n",n,DataBuffer); printf("客户端对刘如通说: "); gets(DataBuffer); printf("\n"); if ((Ret = sendto(NewConnection, DataBuffer, sizeof(DataBuffer),0,(SOCKADDR *)&ClientAddr, &sendlen)) == SOCKET_ERROR)//成功建立连接后向客户端发送数据，结果将显示在客户端上 { printf("发送数据错误 %d\n", WSAGetLastError()); closesocket(NewConnection); WSACleanup(); return; } n++; } printf("成功接收数据字节数 %d byte(s).\n", Ret); printf("准备关闭连接.\n"); closesocket(NewConnection); //将本次建立连接中得到套接字关闭 WSACleanup(); //终止对winsocket库的使用 }