Attempt to resurrect my old triplet ideas with new data types and native methods.

NTwain.sln

@@ -26,6 +26,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "NTwain-temp", "src\NTwain-t
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Console32", "samples\Console32\Console32.csproj", "{AAF9FE1B-B695-4AFD-A014-CA4DFDD06A79}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "WinForm32", "samples\WinForm32\WinForm32.csproj", "{7792A94E-D0B4-440D-8BD5-CA1CA548782C}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -43,12 +45,17 @@ Global
 		{AAF9FE1B-B695-4AFD-A014-CA4DFDD06A79}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{AAF9FE1B-B695-4AFD-A014-CA4DFDD06A79}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{AAF9FE1B-B695-4AFD-A014-CA4DFDD06A79}.Release|Any CPU.Build.0 = Release|Any CPU
+		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{7792A94E-D0B4-440D-8BD5-CA1CA548782C}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
 	EndGlobalSection
 	GlobalSection(NestedProjects) = preSolution
 		{AAF9FE1B-B695-4AFD-A014-CA4DFDD06A79} = {707B4313-8EF8-4D0F-A95E-590783422187}
+		{7792A94E-D0B4-440D-8BD5-CA1CA548782C} = {707B4313-8EF8-4D0F-A95E-590783422187}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {7459323B-44F6-4E07-8574-E1B4B525086B}

samples/Console32/Console32.csproj

@@ -2,11 +2,11 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net7.0</TargetFramework>
+    <TargetFrameworks>net462;net7.0</TargetFrameworks>
-    <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
     <PlatformTarget>x86</PlatformTarget>
     <RootNamespace>SampleConsole</RootNamespace>
+	  <LangVersion>11</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>

samples/Console32/Program.cs

@@ -1,5 +1,8 @@
 using NTwain;
+using System;
+using System.Diagnostics;
 using System.Reflection;
+using TWAINWorkingGroup;
 
 namespace SampleConsole
 {
@@ -7,8 +10,20 @@ namespace SampleConsole
   {
     static void Main(string[] args)
     {
-      var twain = new TwainSession(Environment.ProcessPath ?? Assembly.GetExecutingAssembly().Location);
+      TwainPlatform.PreferLegacyDSM = true;
+
+      var twain = new TwainSession(Assembly.GetExecutingAssembly().Location);
       twain.StateChanged += Twain_StateChanged;
+
+      var hwnd = IntPtr.Zero;
+      var rc = twain.DGControl.Parent.OpenDSM(ref hwnd);
+      Debug.WriteLine($"OpenDSM={rc}");
+
+      if (rc == TWAINWorkingGroup.STS.SUCCESS)
+      {
+        Debug.WriteLine($"CloseDSM={rc}");
+        rc = twain.DGControl.Parent.CloseDSM(ref hwnd);
+      }
     }
 
     private static void Twain_StateChanged(TwainSession session, TWAINWorkingGroup.STATE state)

samples/WinForm32/Form1.Designer.cs

@@ -0,0 +1,39 @@
+namespace WinForm32
+{
+  partial class Form1
+  {
+    /// <summary>
+    ///  Required designer variable.
+    /// </summary>
+    private System.ComponentModel.IContainer components = null;
+
+    /// <summary>
+    ///  Clean up any resources being used.
+    /// </summary>
+    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
+    protected override void Dispose(bool disposing)
+    {
+      if (disposing && (components != null))
+      {
+        components.Dispose();
+      }
+      base.Dispose(disposing);
+    }
+
+    #region Windows Form Designer generated code
+
+    /// <summary>
+    ///  Required method for Designer support - do not modify
+    ///  the contents of this method with the code editor.
+    /// </summary>
+    private void InitializeComponent()
+    {
+      this.components = new System.ComponentModel.Container();
+      this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
+      this.ClientSize = new System.Drawing.Size(800, 450);
+      this.Text = "Form1";
+    }
+
+    #endregion
+  }
+}

samples/WinForm32/Form1.cs

@@ -0,0 +1,51 @@
+using NTwain;
+using System;
+using System.Diagnostics;
+using System.Reflection;
+using System.Windows.Forms;
+using TWAINWorkingGroup;
+
+namespace WinForm32
+{
+  public partial class Form1 : Form
+  {
+    private TwainSession twain;
+
+    public Form1()
+    {
+      InitializeComponent();
+
+      InitTwain();
+    }
+
+    private void InitTwain()
+    {
+      TwainPlatform.PreferLegacyDSM = true;
+
+      twain = new TwainSession(Assembly.GetExecutingAssembly().Location);
+      twain.StateChanged += Twain_StateChanged;
+
+    }
+
+    private static void Twain_StateChanged(TwainSession session, TWAINWorkingGroup.STATE state)
+    {
+      Console.WriteLine($"State changed to {state}");
+    }
+
+    protected override void OnHandleCreated(EventArgs e)
+    {
+      base.OnHandleCreated(e);
+
+
+      var hwnd = this.Handle;
+      var rc = twain.DGControl.Parent.OpenDSM(ref hwnd);
+      Debug.WriteLine($"OpenDSM={rc}");
+
+      if (rc == TWAINWorkingGroup.STS.SUCCESS)
+      {
+        Debug.WriteLine($"CloseDSM={rc}");
+        rc = twain.DGControl.Parent.CloseDSM(ref hwnd);
+      }
+    }
+  }
+}

samples/WinForm32/Form1.resx

@@ -0,0 +1,120 @@
+<?xml version="1.0" encoding="utf-8"?>
+<root>
+  <!-- 
+    Microsoft ResX Schema 
+    
+    Version 2.0
+    
+    The primary goals of this format is to allow a simple XML format 
+    that is mostly human readable. The generation and parsing of the 
+    various data types are done through the TypeConverter classes 
+    associated with the data types.
+    
+    Example:
+    
+    ... ado.net/XML headers & schema ...
+    <resheader name="resmimetype">text/microsoft-resx</resheader>
+    <resheader name="version">2.0</resheader>
+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
+    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>
+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
+        <value>[base64 mime encoded serialized .NET Framework object]</value>
+    </data>
+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
+        <comment>This is a comment</comment>
+    </data>
+                
+    There are any number of "resheader" rows that contain simple 
+    name/value pairs.
+    
+    Each data row contains a name, and value. The row also contains a 
+    type or mimetype. Type corresponds to a .NET class that support 
+    text/value conversion through the TypeConverter architecture. 
+    Classes that don't support this are serialized and stored with the 
+    mimetype set.
+    
+    The mimetype is used for serialized objects, and tells the 
+    ResXResourceReader how to depersist the object. This is currently not 
+    extensible. For a given mimetype the value must be set accordingly:
+    
+    Note - application/x-microsoft.net.object.binary.base64 is the format 
+    that the ResXResourceWriter will generate, however the reader can 
+    read any of the formats listed below.
+    
+    mimetype: application/x-microsoft.net.object.binary.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
+            : and then encoded with base64 encoding.
+    
+    mimetype: application/x-microsoft.net.object.soap.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
+            : and then encoded with base64 encoding.
+
+    mimetype: application/x-microsoft.net.object.bytearray.base64
+    value   : The object must be serialized into a byte array 
+            : using a System.ComponentModel.TypeConverter
+            : and then encoded with base64 encoding.
+    -->
+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
+    <xsd:element name="root" msdata:IsDataSet="true">
+      <xsd:complexType>
+        <xsd:choice maxOccurs="unbounded">
+          <xsd:element name="metadata">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" />
+              </xsd:sequence>
+              <xsd:attribute name="name" use="required" type="xsd:string" />
+              <xsd:attribute name="type" type="xsd:string" />
+              <xsd:attribute name="mimetype" type="xsd:string" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="assembly">
+            <xsd:complexType>
+              <xsd:attribute name="alias" type="xsd:string" />
+              <xsd:attribute name="name" type="xsd:string" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="data">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />
+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />
+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="resheader">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" />
+            </xsd:complexType>
+          </xsd:element>
+        </xsd:choice>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:schema>
+  <resheader name="resmimetype">
+    <value>text/microsoft-resx</value>
+  </resheader>
+  <resheader name="version">
+    <value>2.0</value>
+  </resheader>
+  <resheader name="reader">
+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <resheader name="writer">
+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+</root>

samples/WinForm32/Program.cs

@@ -0,0 +1,20 @@
+using System;
+using System.Windows.Forms;
+
+namespace WinForm32
+{
+  internal static class Program
+  {
+    /// <summary>
+    ///  The main entry point for the application.
+    /// </summary>
+    [STAThread]
+    static void Main()
+    {
+      // To customize application configuration such as set high DPI settings or default font,
+      // see https://aka.ms/applicationconfiguration.
+      ApplicationConfiguration.Initialize();
+      Application.Run(new Form1());
+    }
+  }
+}

samples/WinForm32/WinForm32.csproj

@@ -0,0 +1,15 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+	<PropertyGroup>
+		<OutputType>WinExe</OutputType>
+		<TargetFramework>net6.0-windows</TargetFramework>
+		<Nullable>enable</Nullable>
+		<UseWindowsForms>true</UseWindowsForms>
+		<PlatformTarget>x86</PlatformTarget>
+	</PropertyGroup>
+
+	<ItemGroup>
+	  <ProjectReference Include="..\..\src\NTwain\NTwain.csproj" />
+	</ItemGroup>
+
+</Project>

src/NTwain/TWAINWorkingGroup/TWAINH_EXTRAS.cs

@@ -14,7 +14,7 @@ namespace TWAINWorkingGroup
   {
     static TwainPlatform()
     {
-      Is64bit = IntPtr.Size == 8;
+      Is32bit = IntPtr.Size == 4;
 
 #if NETFRAMEWORK
       if (Environment.OSVersion.Platform == PlatformID.Win32NT)
@@ -64,7 +64,14 @@ namespace TWAINWorkingGroup
     /// <summary>
     /// Whether the code is running in 64bit or 32bit.
     /// </summary>
-    public static bool Is64bit { get; }
+    public static bool Is32bit { get; }
+
+    /// <summary>
+    /// Whether to use the older DSM lib on Windows and Mac. 
+    /// On Windows it only takes effect when running in 32bit. 
+    /// Defaults to false.
+    /// </summary>
+    public static bool PreferLegacyDSM { get; set; }
   }
 
   /// <summary>

src/NTwain/Triplets/DATParent.cs

@@ -0,0 +1,85 @@
+using System;
+using TWAINWorkingGroup;
+
+namespace NTwain.Triplets
+{
+  /// <summary>
+  /// Contains calls used with <see cref="DG.CONTROL"/> and <see cref="DAT.PARENT"/>.
+  /// </summary>
+  public class DATParent : TripletBase
+  {
+    public DATParent(TwainSession session) : base(session)
+    {
+    }
+
+    /// <summary>
+    /// Loads and opens the DSM.
+    /// </summary>
+    /// <param name="hwnd">Required if on Windows.</param>
+    /// <returns></returns>
+    public STS OpenDSM(ref IntPtr hwnd)
+    {
+      STS rc;
+      if ((rc = DoIt(MSG.OPENDSM, ref hwnd)) == STS.SUCCESS)
+      {
+        Session.State = STATE.S3;
+      }
+      return rc;
+    }
+
+    /// <summary>
+    /// Closes the DSM.
+    /// </summary>
+    /// <param name="hwnd">Required if on Windows.</param>
+    /// <returns></returns>
+    public STS CloseDSM(ref IntPtr hwnd)
+    {
+      STS rc;
+      if ((rc = DoIt(MSG.CLOSEDSM, ref hwnd)) == STS.SUCCESS)
+      {
+        Session.State = STATE.S2;
+      }
+      return rc;
+    }
+
+
+    STS DoIt(MSG msg, ref IntPtr hwnd)
+    {
+      var rc = STS.FAILURE;
+      if (TwainPlatform.IsWindows)
+      {
+        var app = Session._appIdentityLegacy;
+        if (TwainPlatform.Is32bit && TwainPlatform.PreferLegacyDSM)
+        {
+          rc = (STS)NativeMethods.WindowsTwain32DsmEntryParent(ref app, IntPtr.Zero, DG.CONTROL, DAT.PARENT, msg, ref hwnd);
+        }
+        else
+        {
+          rc = (STS)NativeMethods.WindowsTwaindsmDsmEntryParent(ref app, IntPtr.Zero, DG.CONTROL, DAT.PARENT, msg, ref hwnd);
+        }
+        if (rc == STS.SUCCESS) Session._appIdentity = app;
+      }
+      else if (TwainPlatform.IsLinux)
+      {
+        var app = Session._appIdentityLegacy;
+
+        rc = (STS)NativeMethods.LinuxDsmEntryParent(ref app, IntPtr.Zero, DG.CONTROL, DAT.PARENT, msg, ref hwnd);
+        if (rc == STS.SUCCESS) Session._appIdentity = app;
+      }
+      else if (TwainPlatform.IsMacOSX)
+      {
+        var app = Session._appIdentityOSX;
+        if (TwainPlatform.PreferLegacyDSM)
+        {
+          rc = (STS)NativeMethods.MacosxTwainDsmEntryParent(ref app, IntPtr.Zero, DG.CONTROL, DAT.PARENT, msg, ref hwnd);
+        }
+        else
+        {
+          rc = (STS)NativeMethods.MacosxTwaindsmDsmEntryParent(ref app, IntPtr.Zero, DG.CONTROL, DAT.PARENT, msg, ref hwnd);
+        }
+        if (rc == STS.SUCCESS) Session._appIdentityOSX = app;
+      }
+      return rc;
+    }
+  }
+}

src/NTwain/Triplets/DGAudio.cs

@@ -0,0 +1,14 @@
+using TWAINWorkingGroup;
+
+namespace NTwain.Triplets
+{
+  /// <summary>
+  /// Contains calls used with <see cref="DG.AUDIO"/>.
+  /// </summary>
+  public class DGAudio : TripletBase
+  {
+    public DGAudio(TwainSession session) : base(session)
+    {
+    }
+  }
+}

src/NTwain/Triplets/DGControl.cs

@@ -0,0 +1,16 @@
+namespace NTwain.Triplets
+{
+  /// <summary>
+  /// Contains calls used with <see cref="DG.CONTROL"/>.
+  /// </summary>
+  public class DGControl : TripletBase
+  {
+    public DGControl(TwainSession session) : base(session)
+    {
+    }
+
+    private DATParent? _parent;
+    public DATParent Parent => _parent ??= new DATParent(Session);
+
+  }
+}

src/NTwain/Triplets/DGImage.cs

@@ -0,0 +1,14 @@
+using TWAINWorkingGroup;
+
+namespace NTwain.Triplets
+{
+  /// <summary>
+  /// Contains calls used with <see cref="DG.IMAGE"/>.
+  /// </summary>
+  public class DGImage : TripletBase
+  {
+    public DGImage(TwainSession session) : base(session)
+    {
+    }
+  }
+}

src/NTwain/Triplets/Readme.md

@@ -0,0 +1,22 @@
+All TWAIN operations are done through the a combination of 
+Data Group (DG), Data Argument Type (DAT), and Message (MSG) 
+triplets. Rather than letting consumers of this lib deal 
+with all the combinations themselves and risk passing the 
+wrong thing, all valid triplet combinations are simply 
+made available under this namespace.
+
+Example:
+To get the status of the DS, just use the 
+"Get" method (represents MSG), in the
+"Status" property (represnts DAT), in the
+"DGControl" class (represents DG).
+
+or better explained in code:
+
+DGControl.Status.Get(...)
+
+Only triplets usable by the
+application-side are defined here.
+
+Due to the number of things involved, the properties are 
+lazy-loaded until used.

src/NTwain/Triplets/TripletBase.cs

@@ -0,0 +1,25 @@
+using System;
+
+namespace NTwain.Triplets
+{
+  /// <summary>
+  /// Base class for grouping triplet operations messages.
+  /// </summary>
+  public abstract class TripletBase
+  {
+    /// <summary>
+    /// Initializes a new instance of the <see cref="TripletBase" /> class.
+    /// </summary>
+    /// <param name="session">The session.</param>
+    /// <exception cref="System.ArgumentNullException"></exception>
+    public TripletBase(TwainSession session)
+    {
+      Session = session ?? throw new ArgumentNullException("session");
+    }
+
+    /// <summary>
+    /// Gets the twain session.
+    /// </summary>
+    public TwainSession Session { get; }
+  }
+}

src/NTwain/TwainSession.PropEvents.cs

@@ -1,4 +1,5 @@
-using System;
+using NTwain.Triplets;
+using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
@@ -42,7 +43,7 @@ namespace NTwain
     public STATE State
     {
       get => _state;
-      private set
+      internal set
       {
         if (_state != value)
         {
@@ -53,8 +54,21 @@ namespace NTwain
     }
 
     /// <summary>
-    /// Fired when state changes.
+    /// Fired when <see cref="State"/> changes.
     /// </summary>
     public event Action<TwainSession, STATE>? StateChanged;
+
+    /// <summary>
+    /// TWAIN triplet API calls with <see cref="DG.CONTROL"/>.
+    /// </summary>
+    public DGControl DGControl { get; }
+    /// <summary>
+    /// TWAIN triplet API calls with <see cref="DG.IMAGE"/>.
+    /// </summary>
+    public DGImage DGImage { get; }
+    /// <summary>
+    /// TWAIN triplet API calls with <see cref="DG.AUDIO"/>.
+    /// </summary>
+    public DGAudio DGAudio { get; }
   }
 }

src/NTwain/TwainSession.cs

@@ -1,4 +1,5 @@
-using System;
+using NTwain.Triplets;
+using System;
 using System.Diagnostics;
 using System.Text;
 using TWAINWorkingGroup;
@@ -62,7 +63,7 @@ namespace NTwain
         ProductName = productName,
         ProtocolMajor = (ushort)TWON_PROTOCOL.MAJOR,
         ProtocolMinor = (ushort)TWON_PROTOCOL.MINOR,
-        SupportedGroups = (uint)(supportedTypes | DG.APP2),
+        SupportedGroups = (uint)(supportedTypes | DG.CONTROL | DG.APP2),
         Version = new TW_VERSION
         {
           Country = appCountry,
@@ -74,6 +75,10 @@ namespace NTwain
       };
       if (TwainPlatform.IsLinux) _appIdentity = _appIdentityLegacy;
       else if (TwainPlatform.IsMacOSX) _appIdentityOSX = _appIdentityLegacy;
+
+      DGControl = new DGControl(this);
+      DGImage = new DGImage(this);
+      DGAudio = new DGAudio(this);
     }
   }
 }