异步消息的网络程序，总是发送数据失败，求解答!

C/C++ code

    DWORD dwIP;    CString strSend;    WSABUF wsabuf;    DWORD dwSend= 0;    int len;    SOCKADDR_IN addrTo;    CString strHostName;    HOSTENT* pHost;    if(GetDlgItemText(IDC_EDIT_HOSTNAME,strHostName),strHostName=="")    {        ((CIPAddressCtrl*)GetDlgItem(IDC_IPADDRESS1))->GetAddress(dwIP);        addrTo.sin_addr.S_un.S_addr=htonl(dwIP);    }    else    {        USES_CONVERSION;        LPSTR stt = W2A(strHostName);        pHost=gethostbyname(stt);        addrTo.sin_addr.S_un.S_addr=*((DWORD*)pHost->h_addr_list[0]);    }    addrTo.sin_family=AF_INET;    addrTo.sin_port=htons(6043);    GetDlgItemText(IDC_EDIT_SEND,strSend);    len=strSend.GetLength();    WideCharToMultiByte(CP_ACP,0,strSend.GetBuffer(len),-1,NULL,0,NULL,FALSE);    USES_CONVERSION;    wsabuf.buf = W2A(strSend.GetBuffer(len));    wsabuf.len=len+1;    if(SOCKET_ERROR==WSASendTo(m_socket,&wsabuf,1,&dwSend,0,        (SOCKADDR*)&addrTo,sizeof(SOCKADDR),NULL,NULL))    {        MessageBox(_T("发送数据失败！"));        return ;    }     SetDlgItemText(IDC_EDIT_SEND,_T(""));

总是发送数据失败唔。这段代码有错误吗？

[解决办法]
m_socket异常