private void DataReceivedCallback(System.IAsyncResult ar)
{
// Retrieve the state object and the client socket
// from the asynchronous state object.
SocketStateObject StateObject = (SocketStateObject)ar.AsyncState;
//* If the socket was closed, then we cannot do anything
if (!StateObject.WorkSocket.Connected)
{
return;
}
//* Get the number of bytes read and add it to the state object accumulator
try
{
//* Add the byte count to the state object
StateObject.CurrentIndex += StateObject.WorkSocket.EndReceive(ar);
}
catch (Exception ex)
{
//* Return an error code
OnComError("Socket Error : " + ex.Message);
return;
}
lock (DataReceivedLock)
{
// Console.WriteLine("DataReceived Received - Index=" & StateObject.CurrentIndex)
//*************************************************************************************************************************
int i = 0;
byte CurrentByte = 0;
while (i < StateObject.CurrentIndex)
{
CurrentByte = StateObject.data[i];
if (CurrentByte == m_TerminatingByteValue)
{
byte[] dataArray = ReceivedDataPacketBuilder.ToArray();
string dataString = string.Empty;
for (var index2 = 0; index2 < dataArray.Length; index2++)
{
if (dataArray[index2] >= 32 && dataArray[index2] < 128)
{
dataString += Microsoft.VisualBasic.Strings.Chr(dataArray[index2]).ToString();
}
}
OnDataReceived(new GenericTcpEventArgs(dataArray, dataString));
CurrentByte = 0; //make sure last byte isn't falsely 16
ReceivedDataPacketBuilder.Clear();
}
else
{
ReceivedDataPacketBuilder.Add(CurrentByte);
}
i += 1;
}
}
SocketStateObject so = new SocketStateObject(WorkSocket);
WorkSocket.BeginReceive(so.data, 0, so.data.Length, SocketFlags.None, DataReceivedCallback, so);
}
//*********************************************
//* Connect to the socket and begin listening
//* for responses
//********************************************
private void Connect()
{
System.Net.IPEndPoint endPoint = null;
System.Net.IPHostEntry IP = null;
System.Net.IPAddress address = new System.Net.IPAddress(0);
if (System.Net.IPAddress.TryParse(m_IPAddress, out address))
{
endPoint = new System.Net.IPEndPoint(address, m_Port);
}
else
{
try
{
IP = System.Net.Dns.GetHostEntry(m_IPAddress);
//* Ethernet/IP uses port AF12 (44818)
endPoint = new System.Net.IPEndPoint(IP.AddressList[0], m_Port);
}
catch (Exception ex)
{
throw new FormatException("Can't resolve the address " + m_IPAddress);
return;
}
}
if (WorkSocket == null || !WorkSocket.Connected)
{
if (m_ProtocolType == System.Net.Sockets.ProtocolType.Tcp)
{
WorkSocket = new System.Net.Sockets.Socket(endPoint.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
//* Comment these out for Compact Framework
WorkSocket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.KeepAlive, 5000);
WorkSocket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.KeepAlive, true);
}
else
{
WorkSocket = new System.Net.Sockets.Socket(endPoint.AddressFamily, SocketType.Dgram, m_ProtocolType);
}
WorkSocket.SendTimeout = 2000;
WorkSocket.ReceiveBufferSize = 0x5000;
}
try
{
try
{
WorkSocket.Connect(endPoint);
}
catch (SocketException ex)
{
//* Return an error code
OnComError("Could Not Connect to Server : " + ex.Message);
CloseConnection();
throw;
}
OnConnectionEstablished(System.EventArgs.Empty);
StartTestThread();
}
catch (SocketException ex)
{
// 10035 == WSAEWOULDBLOCK
if (ex.NativeErrorCode.Equals(10035))
{
//Throw
}
else
{
throw; //New Exception(m_IPAddress & " " & ex.Message)
}
}
WorkSocket.Blocking = true;
if (m_ProtocolType == System.Net.Sockets.ProtocolType.Tcp)
{
WorkSocket.LingerState = new System.Net.Sockets.LingerOption(true, 1000);
}
//* Don't buffer the data, so it goes out immediately
//* Otherwise packets send really fast will get grouped
//* And the PLC will not respond to all of them
WorkSocket.SendBufferSize = 1;
SocketStateObject so = new SocketStateObject();
so.WorkSocket = WorkSocket;
WorkSocket.BeginReceive(so.data, 0, so.data.Length, SocketFlags.None, DataReceivedCallback, so);
}
