socket编程的小例子(udp).doc

使用vs演示时需要设置一下添加ws2_32.lib具体操作，添加位置 ： “项目”-“属性”，之后出现界面点击输入“输入”后界面如下在“附加依赖项”后添加“ws2_32.lib”即可。服务器端程序#include stdafx.h#include #include using namespace std;void main(void)SOCKET sock;/1.启动SOCKET库，版本为2.0WORD wVersionRequested;WSADATA wsaData;int err;wVersionRequested = MAKEWORD( 2, 0 );err = WSAStartup( wVersionRequested, &wsaData );if ( err != 0 ) coutSocket2.0初始化失败，Exit!;return;if ( LOBYTE( wsaData.wVersion ) != 2 |HIBYTE( wsaData.wVersion ) != 0 ) WSACleanup();return; /2.创建套接字sock = socket(AF_INET,SOCK_DGRAM,0);if (sock = INVALID_SOCKET )coutSocket 创建失败，Exit!;return;/3.绑定sockaddr_in myaddr; /sockaddr_in相当于sockaddr结构memset(&myaddr,0,sizeof(myaddr);myaddr.sin_family=AF_INET;/如果绑定地址不是本机地址或者ADDR_ANY，则recvfrom函数不会正确接收，而是立刻返回 /myaddr.sin_addr.s_addr = inet_addr(192.168.0.7);myaddr.sin_addr.s_addr=ADDR_ANY;/端口号必须和客户发往的端口号一致myaddr.sin_port=htons(7861); bind(sock,(sockaddr*)&myaddr,sizeof(myaddr);int fromlength = sizeof(SOCKADDR);char buf256=;long number=0;while(1)number+;recv(sock,buf,sizeof(buf),0);coutnumber:bufendl;memset(buf,0,sizeof(buf);if (!closesocket(sock) WSAGetLastError();return;if (!WSACleanup()WSAGetLastError();return;客户端程序：#include stdafx.h#include #include using namespace std;void main()SOCKET sock; /socketchar szMsg = this is a UDP test package;/被发送的字段/1.启动SOCKET库，版本为2.0WORD wVersionRequested;WSADATA wsaData;int err;wVersionRequested = MAKEWORD( 2, 0 );err = WSAStartup(wVersionRequested, &wsaData );if ( err != 0 ) coutSocket2.0初始化失败，Exit!;return;if ( LOBYTE( wsaData.wVersion ) != 2 |HIBYTE( wsaData.wVersion ) != 0 ) WSACleanup( );return; /2.创建socket，sock = socket(AF_INET, /internetwork: UDP, TCP, etcSOCK_DGRAM, /SOCK_DGRAM说明是UDP类型0 /protocol);if (sock = INVALID_SOCKET ) coutSocket 创建失败，Exit!;return;/3.设置发往的地址sockaddr_in addrto; /发往的地址memset(&addrto,0,sizeof(addrto);addrto.sin_family=AF_INET;/以127开头的ip，并且客户和服务器在同一个局域网，服务方都可以接收(相当于广播)；/指定服务方ip的可以接收 addrto.sin_addr.s_addr=inet_addr(127.0.0.1);/当然也可以换成自己机器的确切Ip/端口号必须和服务器绑定的端口号一致addrto.sin_port=htons(7861);int nlen=sizeof(addrto);unsigned int uIndex = 1;while(true)Sleep(1000);/从广播地址发送消息if( sendto(sock,szMsg,strlen(szMsg),0,(sockaddr*)&addrto,nlen)= SOCKET_ERROR )coutWSAGetLastError()endl;elsecoutuIndex+:an UDP