private void EndReceiveFrom(IAsyncResult ir)
{
if (IsListening)
{
UdpState state = ir.AsyncState as UdpState;
try
{
if (ir.IsCompleted)
{
int length = state.Socket.EndReceiveFrom(ir, ref state.Remote);
byte[] btReceived = new byte[length];
Buffer.BlockCopy(state.Buffer, 0, btReceived, 0, length);
OnReceived(new UdpEventArgs(btReceived, state.Remote));
}
}
catch (Exception ex)
{
System.Diagnostics.Trace.WriteLine(DateTime.Now.ToString() + "\t" + ex.Message + ex.Source);
}
finally
{
state.Socket.BeginReceiveFrom(state.Buffer, 0, state.Buffer.Length, SocketFlags.None, ref state.Remote, new AsyncCallback(EndReceiveFrom), state);
}
}
}
public void Listening()
{
IPAddress ip = IPAddress.Any;
try
{
if (this._ip != null)
{
if (!IPAddress.TryParse(this._ip, out ip))
{
throw new ArgumentException("IP地址错误", "Ip");
}
}
_sck.Bind(new IPEndPoint(ip, this._port));
UdpState state = new UdpState();
state.Socket = _sck;
state.Remote = new IPEndPoint(IPAddress.Any, 0);
_sck.BeginReceiveFrom(state.Buffer, 0, state.Buffer.Length, SocketFlags.None, ref state.Remote, new AsyncCallback(EndReceiveFrom), state);
IsListening = true;
}
catch (ArgumentException ex)
{
IsListening = false;
System.Diagnostics.Trace.WriteLine(DateTime.Now.ToString() + "\t" + ex.Message);
throw ex;
}
catch (Exception ex)
{
IsListening = false;
System.Diagnostics.Trace.WriteLine(DateTime.Now.ToString() + "\t" + ex.Message);
throw ex;
}
}