When creating TCP and UDP servers, you can specify which network interface to use.

Added new event delegates to ModbusServer class that pass a reference to the server to the event.

Author: da66en

EasyModbus/ModbusServer.cs

@@ -85,27 +85,40 @@ internal class TCPHandler
         public event NumberOfClientsChanged numberOfClientsChanged;
 
         TcpListener server = null;
-        
+
 
         private List<Client> tcpClientLastRequestList = new List<Client>();
 
         public int NumberOfConnectedClients { get; set; }
 
         public string ipAddress = null;
 
+        /// When making a server TCP listen socket, will listen to this IP address.
+        public IPAddress LocalIPAddress {
+            get { return localIPAddress; }
+        }
+        private IPAddress localIPAddress = IPAddress.Any;
+
+        /// <summary>
+        /// Listen to all network interfaces.
+        /// </summary>
+        /// <param name="port">TCP port to listen</param>
         public TCPHandler(int port)
         {
-            IPAddress localAddr = IPAddress.Any;
-            server = new TcpListener(localAddr, port);
+            server = new TcpListener(LocalIPAddress, port);
             server.Start();
             server.BeginAcceptTcpClient(AcceptTcpClientCallback, null);
         }
 
-        public TCPHandler(string ipAddress, int port)
+        /// <summary>
+        /// Listen to a specific network interface.
+        /// </summary>
+        /// <param name="localIPAddress">IP address of network interface to listen</param>
+        /// <param name="port">TCP port to listen</param>
+        public TCPHandler(IPAddress localIPAddress, int port)
         {
-            this.ipAddress = ipAddress;
-            IPAddress localAddr = IPAddress.Any;
-            server = new TcpListener(localAddr, port);
+            this.localIPAddress = localIPAddress;
+            server = new TcpListener(LocalIPAddress, port);
             server.Start();
             server.BeginAcceptTcpClient(AcceptTcpClientCallback, null);
         }
@@ -311,8 +324,17 @@ public class ModbusServer
         object lockCoils = new object();
         object lockHoldingRegisters = new object();
         private volatile bool shouldStop;
-        
 
+        private IPAddress localIPAddress = IPAddress.Any;
+
+        /// <summary>
+        /// When creating a TCP or UDP socket, the local IP address to attach to.
+        /// </summary>
+        public IPAddress LocalIPAddress
+        {
+            get { return localIPAddress; }
+            set { if (listenerThread == null) localIPAddress = value; }
+        }
 
         public ModbusServer()
         {
@@ -326,15 +348,23 @@ public ModbusServer()
         #region events
         public delegate void CoilsChangedHandler(int coil, int numberOfCoils);
         public event CoilsChangedHandler CoilsChanged;
+        public delegate void CoilsChangedWithServerHandler(ModbusServer server, int coil, int numberOfCoils);
+        public event CoilsChangedWithServerHandler CoilsChangedWithServer;
 
         public delegate void HoldingRegistersChangedHandler(int register, int numberOfRegisters);
         public event HoldingRegistersChangedHandler HoldingRegistersChanged;
+        public delegate void HoldingRegistersChangedWithServerHandler(ModbusServer server, int register, int numberOfRegisters);
+        public event HoldingRegistersChangedWithServerHandler HoldingRegistersChangedWithServer;
 
         public delegate void NumberOfConnectedClientsChangedHandler();
         public event NumberOfConnectedClientsChangedHandler NumberOfConnectedClientsChanged;
+        public delegate void NumberOfConnectedClientsChangedWithServerHandler(ModbusServer server);
+        public event NumberOfConnectedClientsChangedWithServerHandler NumberOfConnectedClientsChangedWithServer;
 
         public delegate void LogDataChangedHandler();
         public event LogDataChangedHandler LogDataChanged;
+        public delegate void LogDataChangedWithServerHandler(ModbusServer server);
+        public event LogDataChangedWithServerHandler LogDataChangedWithServer;
         #endregion
 
         public void Listen()
@@ -379,9 +409,9 @@ private void ListenerThread()
                         udpClient.Close();
                     }
                     catch (Exception) { }
-                }             
-                tcpHandler = new TCPHandler(port);
-                if (debug) StoreLogData.Instance.Store("EasyModbus Server listing for incomming data at Port " + port, System.DateTime.Now);
+                }
+                tcpHandler = new TCPHandler(LocalIPAddress, port);
+                if (debug) StoreLogData.Instance.Store($"EasyModbus Server listing for incomming data at Port {port}, local IP {LocalIPAddress}", System.DateTime.Now);
                 tcpHandler.dataChanged += new TCPHandler.DataChanged(ProcessReceivedData);
                 tcpHandler.numberOfClientsChanged += new TCPHandler.NumberOfClientsChanged(numberOfClientsChanged);
             }
@@ -408,8 +438,9 @@ private void ListenerThread()
             	{
                     if (udpClient == null | PortChanged)
                     {
-                        udpClient = new UdpClient(port);
-                        if (debug) StoreLogData.Instance.Store("EasyModbus Server listing for incomming data at Port " + port, System.DateTime.Now);
+                        IPEndPoint localEndoint = new IPEndPoint(LocalIPAddress, port);
+                        udpClient = new UdpClient(localEndoint);
+                        if (debug) StoreLogData.Instance.Store($"EasyModbus Server listing for incomming data at Port {port}, local IP {LocalIPAddress}", System.DateTime.Now);
                         udpClient.Client.ReceiveTimeout = 1000;
                         iPEndPoint = new IPEndPoint(IPAddress.Any, port);
                         PortChanged = false;                      
@@ -485,6 +516,8 @@ private void numberOfClientsChanged()
             numberOfConnections = tcpHandler.NumberOfConnectedClients;
             if (NumberOfConnectedClientsChanged != null)
                 NumberOfConnectedClientsChanged();
+            if (NumberOfConnectedClientsChangedWithServer != null)
+                NumberOfConnectedClientsChangedWithServer(this);
         }
         #endregion
 
@@ -650,6 +683,8 @@ private void ProcessReceivedData(object networkConnectionParameter)
 
                 if (LogDataChanged != null)
                     LogDataChanged();
+                if (LogDataChangedWithServer != null)
+                    LogDataChangedWithServer(this);
             }
         }
         #endregion
@@ -1390,6 +1425,8 @@ private void WriteSingleCoil(ModbusProtocol receiveData, ModbusProtocol sendData
                 catch (Exception) { }
                 if (CoilsChanged != null)
                     CoilsChanged(receiveData.startingAdress+1, 1);
+                if (CoilsChangedWithServer != null)
+                    CoilsChangedWithServer(this, receiveData.startingAdress + 1, 1);
             }
         }
 
@@ -1513,6 +1550,8 @@ private void WriteSingleRegister(ModbusProtocol receiveData, ModbusProtocol send
                 catch (Exception) { }
                 if (HoldingRegistersChanged != null)
                     HoldingRegistersChanged(receiveData.startingAdress+1, 1);
+                if (HoldingRegistersChangedWithServer != null)
+                    HoldingRegistersChangedWithServer(this, receiveData.startingAdress + 1, 1);
             }
         }
 
@@ -1653,6 +1692,8 @@ private void WriteMultipleCoils(ModbusProtocol receiveData, ModbusProtocol sendD
                 catch (Exception) { }
                 if (CoilsChanged != null)
                     CoilsChanged(receiveData.startingAdress+1, receiveData.quantity);
+                if (CoilsChangedWithServer != null)
+                    CoilsChangedWithServer(this, receiveData.startingAdress + 1, receiveData.quantity);
             }
         }
 
@@ -1777,6 +1818,8 @@ private void WriteMultipleRegisters(ModbusProtocol receiveData, ModbusProtocol s
                 catch (Exception) { }
                 if (HoldingRegistersChanged != null)
                     HoldingRegistersChanged(receiveData.startingAdress+1, receiveData.quantity);
+                if (HoldingRegistersChangedWithServer != null)
+                    HoldingRegistersChangedWithServer(this, receiveData.startingAdress + 1, receiveData.quantity);
             }
         }
 
@@ -1908,6 +1951,8 @@ private void ReadWriteMultipleRegisters(ModbusProtocol receiveData, ModbusProtoc
                 catch (Exception) { }
                 if (HoldingRegistersChanged != null)
                     HoldingRegistersChanged(receiveData.startingAddressWrite+1, receiveData.quantityWrite);
+                if (HoldingRegistersChangedWithServer != null)
+                    HoldingRegistersChangedWithServer(this, receiveData.startingAddressWrite + 1, receiveData.quantityWrite);
             }
         }