Bam. Connections are saving. We're up and running.

src/NModbus.Tools.Base/Behaviors/CloseableBehavior.cs

@@ -0,0 +1,91 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows;
+using System.Windows.Interactivity;
+
+namespace NModbus.Tools.Base.Behaviors
+{
+    /// <summary>
+    /// Provides a simple interface for windows that should be closeable from their view model.
+    /// </summary>
+    public class CloseableBehavior : Behavior<Window>
+    {
+        private ICloseableViewModel _closeable;
+
+        /// <summary>
+        /// Called after the behavior is attached to an AssociatedObject.
+        /// </summary>
+        /// <remarks>
+        /// Override this to hook up functionality to the AssociatedObject.
+        /// </remarks>
+        protected override void OnAttached()
+        {
+            AssociatedObject.Closing += AssociatedObject_Closing;
+            AssociatedObject.DataContextChanged += AssociatedObject_DataContextChanged;
+            AssociatedObject.Closed += AssociatedObject_Closed;
+
+            _closeable = this.AssociatedObject.DataContext as ICloseableViewModel;
+
+            if (_closeable != null)
+                _closeable.Close += Closeable_Close;
+
+            base.OnAttached();
+        }
+
+        /// <summary>
+        /// Called when the behavior is being detached from its AssociatedObject, but before it has actually occurred.
+        /// </summary>
+        /// <remarks>
+        /// Override this to unhook functionality from the AssociatedObject.
+        /// </remarks>
+        protected override void OnDetaching()
+        {
+            base.OnDetaching();
+
+            AssociatedObject.Closing -= AssociatedObject_Closing;
+            AssociatedObject.DataContextChanged -= AssociatedObject_DataContextChanged;
+            AssociatedObject.Closed -= AssociatedObject_Closed;
+        }
+
+        void AssociatedObject_DataContextChanged(object sender, DependencyPropertyChangedEventArgs e)
+        {
+            if (_closeable != null)
+                _closeable.Close -= Closeable_Close;
+
+            _closeable = e.NewValue as ICloseableViewModel;
+
+            if (_closeable != null)
+                _closeable.Close += Closeable_Close;
+        }
+
+        void Closeable_Close(object sender, CloseEventArgs e)
+        {
+            //https://social.msdn.microsoft.com/Forums/vstudio/en-US/c95f1acb-5dee-4670-b779-b07b06afafff/where-is-modal-property?forum=wpf
+            if (System.Windows.Interop.ComponentDispatcher.IsThreadModal)
+            {
+                AssociatedObject.DialogResult = e.DialogResult;
+            }
+
+            AssociatedObject.Close();
+        }
+
+        void AssociatedObject_Closing(object sender, System.ComponentModel.CancelEventArgs e)
+        {
+            if (_closeable != null)
+            {
+                if (!_closeable.CanClose())
+                {
+                    e.Cancel = true;
+                }
+            }
+        }
+
+        void AssociatedObject_Closed(object sender, System.EventArgs e)
+        {
+            _closeable?.Closed();
+        }
+    }
+}

src/NModbus.Tools.Base/Behaviors/ICloseableViewModel.cs

@@ -0,0 +1,46 @@
+using System;
+
+namespace NModbus.Tools.Base.Behaviors
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public interface ICloseableViewModel
+    {
+        /// <summary>
+        /// Fired when the view model requests that its container be closed.
+        /// </summary>
+        event EventHandler<CloseEventArgs> Close;
+
+        /// <summary>
+        /// Returns true if the container can be closed, false otherwise.
+        /// </summary>
+        /// <returns></returns>
+        bool CanClose();
+
+        /// <summary>
+        /// Called when the view has been closed.
+        /// </summary>
+        void Closed();
+    }
+
+    /// <summary>
+    /// 
+    /// </summary>
+    public class CloseEventArgs : EventArgs
+    {
+        /// <summary>
+        /// 
+        /// </summary>
+        /// <param name="dialogResult"></param>
+        public CloseEventArgs(bool? dialogResult)
+        {
+            this.DialogResult = dialogResult;
+        }
+
+        /// <summary>
+        /// 
+        /// </summary>
+        public bool? DialogResult { get; set; }
+    }
+}

src/NModbus.Tools.Base/ConnectionSelectionService.cs

@@ -0,0 +1,78 @@
+using Newtonsoft.Json;
+using NModbus.Tools.Base.Model;
+using NModbus.Tools.Base.View;
+using NModbus.Tools.Base.ViewModel;
+using NModbus.Tools.Interfaces;
+using System;
+using System.IO;
+using System.Windows;
+
+namespace NModbus.Tools.Base
+{
+    public class ConnectionSelectionService : IConnectionSelectionService
+    {
+        private static readonly string FilePath;
+
+        static ConnectionSelectionService()
+        {
+            FilePath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), "NModbus Tools", "connections.json");
+        }
+
+        public Connection GetConnection()
+        {
+            var connections = GetConnections();
+
+            var viewModel = new ConnectionSelectionViewModel(connections);
+
+            var view = new ConnectionSelectionDialog
+            {
+                DataContext = viewModel
+            };
+
+            if (view.ShowDialog() == true)
+            {
+                SaveConnections(viewModel.ToModel());
+
+                return viewModel.SelectedConnection.ToModel();
+            }
+
+            return null;
+        }
+
+        private void SaveConnections(SavedConnections connections)
+        {
+            var json = JsonConvert.SerializeObject(connections);
+
+            var directory = Path.GetDirectoryName(FilePath);
+
+            Directory.CreateDirectory(directory);
+
+            File.WriteAllText(FilePath, json);
+        }
+
+        private SavedConnections GetConnections()
+        {
+            try
+            {
+                var json = File.ReadAllText(FilePath);
+
+                var connections = JsonConvert.DeserializeObject<SavedConnections>(json);
+
+                if (connections.Connections == null)
+                {
+                    connections.Connections = new Connection[] { };
+                }
+
+                return connections;
+            }
+            catch(Exception)
+            {
+                return new SavedConnections
+                {
+                    Connections = new Connection[] { }
+                };
+            }
+
+        }
+    }
+}

src/NModbus.Tools.Base/Model/ConnectionFactory.cs

@@ -5,27 +5,33 @@
 
 namespace NModbus.Tools.Base.Model
 {
-    public class ConnectionFactory
+    public class ConnectionFactory : IModbusMasterFactory
     {
         private const int TcpConnectionTimeoutMilliseconds = 10 * 1000;
+        private readonly Connection _connection;
 
-        public IModbusMaster CreateAsync(Connection connection)
+        public ConnectionFactory(Connection connection)
+        {
+            _connection = connection;
+        }
+
+        public IModbusMaster Create()
         {
             var factory = new ModbusFactory();
 
-            switch (connection.Type)
+            switch (_connection.Type)
             {
                 case ConnectionType.Rtu:
                     {
-                        var serialPort = CreateAndOpenSerialPort(connection);
+                        var serialPort = CreateAndOpenSerialPort(_connection);
 
                         var transport = new SerialPortAdapter(serialPort);
 
                         return factory.CreateRtuMaster(transport);
                     }
                 case ConnectionType.Ascii:
                     {
-                        var serialPort = CreateAndOpenSerialPort(connection);
+                        var serialPort = CreateAndOpenSerialPort(_connection);
 
                         var transport = new SerialPortAdapter(serialPort);
 
@@ -35,9 +41,9 @@ public IModbusMaster CreateAsync(Connection connection)
                     {
                         var tcpClient = new TcpClient();
 
-                        if (!tcpClient.ConnectAsync(connection.HostName, connection.Port).Wait(TcpConnectionTimeoutMilliseconds))
+                        if (!tcpClient.ConnectAsync(_connection.HostName, _connection.Port).Wait(TcpConnectionTimeoutMilliseconds))
                         {
-                            throw new TimeoutException($"Timed out trying to connect to TCP Modbus device at {connection.HostName}:{connection.Port}");
+                            throw new TimeoutException($"Timed out trying to connect to TCP Modbus device at {_connection.HostName}:{_connection.Port}");
                         }
 
                         return factory.CreateMaster(tcpClient);
@@ -49,7 +55,7 @@ public IModbusMaster CreateAsync(Connection connection)
                         return factory.CreateMaster(udpClient);
                     }
                 default:
-                    throw new ArgumentException($"{nameof(connection.Type)} had an unepected value '{connection.Type}'.");
+                    throw new ArgumentException($"{nameof(_connection.Type)} had an unepected value '{_connection.Type}'.");
             }
         }
 
@@ -70,5 +76,26 @@ private SerialPort CreateAndOpenSerialPort(Connection connection)
 
             return serialPort;
         }
+
+        public override string ToString()
+        {
+            switch (_connection.Type)
+            {
+                case ConnectionType.Tcp:
+                    return $"TCP {_connection.HostName}:{_connection.Port}";
+
+                case ConnectionType.Udp:
+                    return $"UDP {_connection.HostName}:{_connection.Port}";
+
+                case ConnectionType.Rtu:
+                    return $"RTU {_connection.SerialPortName} ({_connection.Baud})";
+
+                case ConnectionType.Ascii:
+                    return $"ASCII {_connection.SerialPortName} ({_connection.Baud})";
+
+                default:
+                    return "Unknown Type";
+            }
+        }
     }
 }

src/NModbus.Tools.Base/NModbus.Tools.Base.csproj

@@ -66,8 +66,26 @@
     <Reference Include="System.Net.Http" />
     <Reference Include="System.Xml" />
     <Reference Include="WindowsBase" />
+    <Reference Include="Xceed.Wpf.AvalonDock, Version=3.5.0.0, Culture=neutral, PublicKeyToken=3e4669d2f30244f4, processorArchitecture=MSIL">
+      <HintPath>..\packages\Extended.Wpf.Toolkit.3.5.0\lib\net40\Xceed.Wpf.AvalonDock.dll</HintPath>
+    </Reference>
+    <Reference Include="Xceed.Wpf.AvalonDock.Themes.Aero, Version=3.5.0.0, Culture=neutral, PublicKeyToken=3e4669d2f30244f4, processorArchitecture=MSIL">
+      <HintPath>..\packages\Extended.Wpf.Toolkit.3.5.0\lib\net40\Xceed.Wpf.AvalonDock.Themes.Aero.dll</HintPath>
+    </Reference>
+    <Reference Include="Xceed.Wpf.AvalonDock.Themes.Metro, Version=3.5.0.0, Culture=neutral, PublicKeyToken=3e4669d2f30244f4, processorArchitecture=MSIL">
+      <HintPath>..\packages\Extended.Wpf.Toolkit.3.5.0\lib\net40\Xceed.Wpf.AvalonDock.Themes.Metro.dll</HintPath>
+    </Reference>
+    <Reference Include="Xceed.Wpf.AvalonDock.Themes.VS2010, Version=3.5.0.0, Culture=neutral, PublicKeyToken=3e4669d2f30244f4, processorArchitecture=MSIL">
+      <HintPath>..\packages\Extended.Wpf.Toolkit.3.5.0\lib\net40\Xceed.Wpf.AvalonDock.Themes.VS2010.dll</HintPath>
+    </Reference>
+    <Reference Include="Xceed.Wpf.Toolkit, Version=3.5.0.0, Culture=neutral, PublicKeyToken=3e4669d2f30244f4, processorArchitecture=MSIL">
+      <HintPath>..\packages\Extended.Wpf.Toolkit.3.5.0\lib\net40\Xceed.Wpf.Toolkit.dll</HintPath>
+    </Reference>
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="Behaviors\CloseableBehavior.cs" />
+    <Compile Include="Behaviors\ICloseableViewModel.cs" />
+    <Compile Include="ConnectionSelectionService.cs" />
     <Compile Include="CrcExtensions.cs" />
     <Compile Include="FunctionCodeNameFactory.cs" />
     <Compile Include="FunctionCode.cs" />
@@ -99,12 +117,16 @@
   <ItemGroup>
     <None Include="packages.config" />
   </ItemGroup>
-  <ItemGroup />
   <ItemGroup>
     <Page Include="View\ConnectionSelectionDialog.xaml">
       <SubType>Designer</SubType>
       <Generator>MSBuild:Compile</Generator>
     </Page>
   </ItemGroup>
+  <ItemGroup>
+    <Resource Include="Images\AddLink_16x.png" />
+    <Resource Include="Images\Link_16xMD.png" />
+    <Resource Include="Images\RemoveLink_16x.png" />
+  </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
 </Project>