在VC下如何编写基于UDP协议的点对点的通信，有什么资料吗？

Question

在windows里要用udp协议，实际上就是win socket编程。所用到的函数全在头文件winsocket2.h里

Answer 1

我知道是socket编程。我问那里有资料，现在的资料大多是TCP协议的。

Answer 2

接着
UDP.hclass CUdpComm  
{
public:
UCHAR CRCTest(UCHAR* Buff,int From,int To);
BOOL Send(BYTE* buf,int size,char* addr);
CUdpComm(CWnd* pParent,
UINT nSendPort=16888,
UINT nRecvPort=16889);
virtual ~CUdpComm();
private:
UINT m_nSendPort;
UINT m_nRecvPort; CWnd* m_pParent; static UINT Thread(LPVOID pParam);
BOOL m_bContinue;
BOOL m_bExited;
};

Answer 3

接着
UDP.cpp
CUdpComm::CUdpComm(CWnd* pParent,UINT nSendPort,UINT nRecvPort)
{
m_nSendPort=nSendPort;
m_nRecvPort=nRecvPort;
m_pParent=pParent; WSADATA wsd;
WSAStartup(0x0101,&wsd); m_bContinue=TRUE;
m_bExited=TRUE;
AfxBeginThread(Thread,(LPVOID)this);}CUdpComm::~CUdpComm()
{
// BYTE buf[11];
m_bContinue=FALSE;
/*
while(m_bExited==FALSE)
{
Send(buf,11,"127.0.0.1");
}
*/
//Sleep(500);
WSACleanup();
}BOOL CUdpComm::Send(BYTE *buf, int size,char* addr)
{
CSocket sockSend;
sockSend.Create(m_nSendPort,SOCK_DGRAM,NULL);
sockSend.Bind(m_nSendPort,addr);
int nCount;
nCount=sockSend.SendTo(buf,
size,m_nRecvPort,addr,0);
sockSend.Close();
return TRUE;
}UINT CUdpComm::Thread(LPVOID pParam)
{
CUdpComm* pThis=(CUdpComm*)pParam;
pThis->m_bExited=FALSE;
CSocket sockReceive;
BYTE buf[256];
BYTE* PostBuf; UINT Port=pThis->m_nRecvPort; sockReceive.Create(Port,SOCK_DGRAM,NULL);
sockReceive.Bind(Port,"127.0.0.1");

CString strAddr("127.0.0.1");
UINT nPort=pThis->m_nSendPort; int nCount;
while(pThis->m_bContinue==TRUE)
{
Sleep(100);
nCount=sockReceive.ReceiveFrom(buf,256,strAddr,nPort,0);
PostBuf=new BYTE[nCount];
memcpy(PostBuf,buf,nCount);
pThis->m_pParent->PostMessage(IDM_SOCK_RECEIVE_DATA,
(WPARAM)PostBuf,nCount);
}
sockReceive.Close();
pThis->m_bExited=TRUE;
return 0;
}
//每次校验2~buffersize-1字节内容,不校验55AA
UCHAR CUdpComm::CRCTest(UCHAR* Buff,int From,int To)
{
UCHAR CrcTable[] = {
0x00, 0x07, 0x0E, 0x09, 0x1C, 0x1B, 0x12, 0x15,
0x38, 0x3F, 0x36, 0x31, 0x24, 0x23, 0x2A, 0x2D,
0x70, 0x77, 0x7E, 0x79, 0x6C, 0x6B, 0x62, 0x65,
0x48, 0x4F, 0x46, 0x41, 0x54, 0x53, 0x5A, 0x5D,
0xE0, 0xE7, 0xEE, 0xE9, 0xFC, 0xFB, 0xF2, 0xF5,
0xD8, 0xDF, 0xD6, 0xD1, 0xC4, 0xC3, 0xCA, 0xCD,
0x90, 0x97, 0x9E, 0x99, 0x8C, 0x8B, 0x82, 0x85,
0xA8, 0xAF, 0xA6, 0xA1, 0xB4, 0xB3, 0xBA, 0xBD,
0xC7, 0xC0, 0xC9, 0xCE, 0xDB, 0xDC, 0xD5, 0xD2,
0xFF, 0xF8, 0xF1, 0xF6, 0xE3, 0xE4, 0xED, 0xEA,
0xB7, 0xB0, 0xB9, 0xBE, 0xAB, 0xAC, 0xA5, 0xA2,
0x8F, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9D, 0x9A,
0x27, 0x20, 0x29, 0x2E, 0x3B, 0x3C, 0x35, 0x32,
0x1F, 0x18, 0x11, 0x16, 0x03, 0x04, 0x0D, 0x0A,
0x57, 0x50, 0x59, 0x5E, 0x4B, 0x4C, 0x45, 0x42,
0x6F, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7D, 0x7A,
0x89, 0x8E, 0x87, 0x80, 0x95, 0x92, 0x9B, 0x9C,
0xB1, 0xB6, 0xBF, 0xB8, 0xAD, 0xAA, 0xA3, 0xA4,
0xF9, 0xFE, 0xF7, 0xF0, 0xE5, 0xE2, 0xEB, 0xEC,
0xC1, 0xC6, 0xCF, 0xC8, 0xDD, 0xDA, 0xD3, 0xD4,
0x69, 0x6E, 0x67, 0x60, 0x75, 0x72, 0x7B, 0x7C,
0x51, 0x56, 0x5F, 0x58, 0x4D, 0x4A, 0x43, 0x44,
0x19, 0x1E, 0x17, 0x10, 0x05, 0x02, 0x0B, 0x0C,
0x21, 0x26, 0x2F, 0x28, 0x3D, 0x3A, 0x33, 0x34,
0x4E, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5C, 0x5B,
0x76, 0x71, 0x78, 0x7F, 0x6A, 0x6D, 0x64, 0x63,
0x3E, 0x39, 0x30, 0x37, 0x22, 0x25, 0x2C, 0x2B,
0x06, 0x01, 0x08, 0x0F, 0x1A, 0x1D, 0x14, 0x13,
0xAE, 0xA9, 0xA0, 0xA7, 0xB2, 0xB5, 0xBC, 0xBB,
0x96, 0x91, 0x98, 0x9F, 0x8A, 0x8D, 0x84, 0x83,
0xDE, 0xD9, 0xD0, 0xD7, 0xC2, 0xC5, 0xCC, 0xCB,
0xE6, 0xE1, 0xE8, 0xEF, 0xFA, 0xFD, 0xF4, 0xF3 
};
int i;
UCHAR result = 0;
for(i=From;i<To;i++)
result = CrcTable[Buff[i] ^ result];
return result^0xFF;
}