/// <summary>
/// Send UDP private message to a specific recipient
/// </summary>
/// <param name="txtMsg">UDPDatagram private message</param>
/// <param name="epRemote">Recipient address</param>
public void SendMessage(UdpDatagram txtMsg, IPEndPoint epRemote)
{
byte[] data = new byte[soc.SendBufferSize];
string txtMsgStr = txtMsg.ToString();
int leftLen = txtMsgStr.Length;
int sendLen = 0;
try
{
while (leftLen != 0)
{
if (leftLen >= soc.SendBufferSize)
{
data = Encoding.UTF8.GetBytes(txtMsgStr.Substring(sendLen, soc.SendBufferSize));
soc.SendTo(data, soc.SendBufferSize, SocketFlags.None, epRemote);
leftLen -= soc.SendBufferSize;
sendLen += soc.SendBufferSize;
}
else
{
data = Encoding.UTF8.GetBytes(txtMsgStr.Substring(sendLen, leftLen));
soc.SendTo(data, leftLen, SocketFlags.None, epRemote);
leftLen = 0;
}
}
}
catch (Exception ex)
{
if (SendFail != null)
{
SendFail(String.Format("Message Send Failed! " + ex.Message));
}
}
}
/// <summary>
/// Convert the network string to UdpDatagram
/// </summary>
/// <param name="netstr">Received network string</param>
/// <returns>UdpDatagram Object</returns>
public static UdpDatagram Convert(string netstr)
{
UdpDatagram data = new UdpDatagram();
int ChCount = 0;
int netstrLen = netstr.Length;
int headfieldcount = 1;
string typestr = "";
string fromAddrstr = "";
string toAddrstr = "";
string hostnamestr = "";
string hostnameLenstr = "";
int hostnameLen = 0;
string messagestr = "";
for (; ChCount < netstrLen && headfieldcount != 6; ChCount++) //Extract all the headerfields
{
if (headfieldcount != 6 && netstr[ChCount] == ',')
{
if (headfieldcount == 4)
{
hostnameLen = int.Parse(hostnameLenstr);
}
headfieldcount++;
}
else if (netstr[ChCount] != ',')
{
switch (headfieldcount)
{
case 1: typestr += netstr[ChCount]; break;
case 2: fromAddrstr += netstr[ChCount]; break;
case 3: toAddrstr += netstr[ChCount]; break;
case 4: hostnameLenstr += netstr[ChCount]; break;
case 5: hostnamestr = netstr.Substring(ChCount, hostnameLen); ChCount += hostnameLen - 1; break;
}
}
}
if (ChCount < netstrLen)
{
messagestr = netstr.Substring(ChCount);
}
data.Type = (UdpDatagramType)Enum.Parse(typeof(UdpDatagramType), typestr);
data.FromAddress = fromAddrstr;
data.ToAddress = toAddrstr;
data.HostName = hostnamestr;
data.Message = messagestr;
return(data);
}
/// <summary>
/// Receive UDP message and call the corresponding event handler
/// </summary>
private void ListenIncomingMsg()
{
byte[] buffer = new byte[soc.ReceiveBufferSize];
EndPoint remoteEP = new IPEndPoint(IPAddress.Any, 0);
try
{
while (true)
{
int len = soc.ReceiveFrom(buffer, ref remoteEP);
UdpDatagram msg = UdpDatagram.Convert(Encoding.UTF8.GetString(buffer, 0, len));
switch (msg.Type)
{
case UdpDatagramType.Chat: RemoteMessageReceived(msg.HostName, IPAddress.Parse(msg.FromAddress), msg.Message); break;
case UdpDatagramType.OnLine: RemoteOnLine(msg.HostName, IPAddress.Parse(msg.FromAddress)); break;
case UdpDatagramType.OffLine: RemoteOffLine(msg.HostName, IPAddress.Parse(msg.FromAddress)); break;
case UdpDatagramType.FAccept: FileAccept(msg.HostName, msg.Message, IPAddress.Parse(msg.FromAddress)); break;
case UdpDatagramType.FRefuse: FileRefuse(msg.HostName, msg.Message, IPAddress.Parse(msg.FromAddress)); break;
case UdpDatagramType.FSendReq: FileSendReq(msg.HostName, msg.Message, IPAddress.Parse(msg.FromAddress)); break;
}
}
}
catch (SocketException)
{
}
catch (ThreadAbortException)
{
}
catch (Exception e)
{
MessageBox.Show(String.Format("Error Type:{0};Message:{1}", e.GetType(), e.Message));
}
}
/// <summary>
/// Send UDP group message to all users
/// </summary>
/// <param name="Msg">UDPDatagram group message</param>
/// <param name="groupEP">Multicast group address</param>
public void MultiCast(UdpDatagram Msg, IPEndPoint groupEP)
{
byte[] msg = Encoding.UTF8.GetBytes(Msg.ToString());
soc.SendTo(msg, groupEP);
}
