CAsyncSocket发广播包

1.#include <afxsock.h>

2.定义CAsyncSocket类的指针

CAsyncSocket　*pSocket;

3.初始化Socket

if (!AfxSocketInit())
{
   AfxMessageBox("Error");//IDP_SOCKETS_INIT_FAILED
   return FALSE;
}

4.初始化pSocket

pSocket = new CAsyncSocket;

pSocket->Create(1207, SOCK_DGRAM);

5.发送广播包

设置SO_BROADCAST属性为TRUE。

BOOL bBroadcast = TRUE;
pSocket->SetSockOpt(SO_BROADCAST,(char *)&bBroadcast,sizeof(BOOL));

发送：

sockaddr_in local;
int len = sizeof(local);
memset(&local, 0, len);
local.sin_family = AF_INET;
local.sin_port = htons(9371);//htons(dwPort);
local.sin_addr.s_addr = htonl(INADDR_BROADCAST);
if (pSocket->SendTo(data,32,(const SOCKADDR*)&local,len) == SOCKET_ERROR)
{
      pSocket->GetLastError();
}