1、 線程中建立連接配接，斷開時自動會重連
SOCKET g_socket;
DWORD WINAPIThreadConnectDevice(LPVOID wParam)
{
uint16_t port = 42000; // Default is UDP port 42000
while(1)
{
intret = startUDPConnection(port, &g_socket);
if(ret == RESULT_OK)
{
Receiver(&g_socket);//接收處理
stopUDPConnection(&g_socket);
}
else
{
Sleep(10);
}
}
}
return 0;
}
（2）startUDPConnection
int startUDPConnection(uint16_t port, SOCKET*pSocket)
{
WSADATA wsa;
SOCKADDR_IN addr;
int ret;
int rc;
// Start Winsock
ret = WSAStartup(MAKEWORD(2,0),&wsa);
if (ret !=0)
{
TRACE("Can'tstart Windows Socks API\n");
returnRESULT_ERROR;
}
// create socket
*pSocket = socket(AF_INET,SOCK_DGRAM,0);
if(*pSocket== INVALID_SOCKET)
{
TRACE("Coudln'tcreate the UDP socket\n");
returnRESULT_ERROR;
}
// bind socket toport
addr.sin_family=AF_INET;
addr.sin_port=htons(port);
addr.sin_addr.s_addr=ADDR_ANY;
rc=bind(*pSocket,(SOCKADDR*)&addr,sizeof(SOCKADDR_IN));
if(rc==SOCKET_ERROR)
{
TRACE("Binddidn't work, error code: %d\n",WSAGetLastError());
returnRESULT_ERROR;
}
returnRESULT_OK;
}
（3）資料接收
int Receiver(SOCKET* pSocket)
{
// holds thesender information of the received packet
structsockaddr remoteAddr;
int32_t remoteAddrLen;
// buffer for asingle UDP packet
int8_t udpPacketBuf[UDP_PACKET_BUF_LEN];
remoteAddrLen=sizeof(struct sockaddr);
// run for alleternity as long as no error occurs
while (1)
{
// receivethe data. rc contains the number of received bytes and also the error code
// IMPORTANT:This is a blocking call. If it doesn't receive anything it will wait forever
int32_t rc=recvfrom(*pSocket,(char*)udpPacketBuf,UDP_PACKET_BUF_LEN,0,&remoteAddr,&remoteAddrLen);
if(rc==SOCKET_ERROR)
{
TRACE("Errorin recvfrom, error code: %d\n",WSAGetLastError());
returnRESULT_ERROR;
}
else
{
//對接收資料的處理
}
}
returnRESULT_OK;
}
（4）關閉連接配接
void stopUDPConnection(SOCKET* pSocket)
{
closesocket(*pSocket);
WSACleanup();
}