Get Twain Capability

Take the following steps to start a project and to add some code to get a Twain Capability:

Start Visual Studio .NET.
Choose File->New->Project… from the menu.
In the New Project dialog box, choose either "Visual C# Projects" or "Visual Basic Projects" in the Projects Type List, and choose "Windows Application " in the Templates List.
Type the project name as "GetTwainCapability" in the Project Name field, and then choose OK. If desired, type a new location for your project or select a directory using the Browse button, and then choose OK .
In the "Solution Explorer" window, right-click on the "References" folder, and select "Add Reference…" from the context menu. In the "Add Reference" dialog box, select the ".NET" tab and browse to Leadtools For .NET "\LEAD Technologies\LEADTOOLS 16.5\Bin\DotNet\Win32 " folder and select the following DLLs:
- Leadtools.dll
- Leadtools.Twain.dll
- Leadtools.Codecs.dll
- Leadtools.WinForms.dll
Click the Select button and then press the OK button to add the above DLLs to the application.
Go to the toolbox (View->Toolbox) and Drag and drop a 4 instance of Button control to the top of the form and set the following properties for them:

Text Name

Select Source buttonSelectSource

Use Capability buttonUseCapability

Set Brightness buttonSetBrightness

Acquire buttonAcquire

Text	Name
Select Source	buttonSelectSource
Use Capability	buttonUseCapability
Set Brightness	buttonSetBrightness
Acquire	buttonAcquire

Switch to Form1 code view (right-click Form1 in the solution explorer then select View Code ) and add the following lines at the beginning of the file:

[Visual Basic]

 
Imports Leadtools
Imports Leadtools.Twain
Imports Leadtools.Codecs
Imports Leadtools.WinForms

[C#]

 
using Leadtools;
using Leadtools.Twain;
using Leadtools.Codecs;
using Leadtools.WinForms;

Declare the following private variable:

[Visual Basic]

 
Private WithEvents twnSession As TwainSession

[C#]

 
private TwainSession twnSession;

Add an event handler to the Form1 Load event and code it as follows:

[Visual Basic]

 
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
   Try
      ' Unlock Document support.
      ' Note that this is a sample key, which will not work in your toolkit.
      RasterSupport.Unlock(RasterSupportType.Document, "TestKey")

      twnSession = new TwainSession
      twnSession.Startup(Me, "LEAD Technologies, Inc.", "LEAD TWAIN .NET", "Version 16", "LEADTOOLS TWAIN test sample", TwainStartupFlags.None)
   Catch ex As Exception
      MessageBox.Show(ex.Message)
   End Try
End Sub

[C#]

 
private void Form1_Load(object sender, System.EventArgs e)
{
   try
   {
      // Unlock Document support.
      // Note that this is a sample key, which will not work in your toolkit.
      RasterSupport.Unlock(RasterSupportType.Document, "TestKey");

      twnSession = new TwainSession();
      twnSession.Startup(this, "LEAD Technologies, Inc.", "LEAD Twain .NET", "Version 14", "LEADTools Twain test sample", TwainStartupFlags.None);
   }
   catch (Exception ex)
   {
      MessageBox.Show(this, ex.Message);
   }
}

Add an event handler to the Form1 Closing event and code it as follows:

[Visual Basic]

 
Private Sub Form1_FormClosing(ByVal sender As System.Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles MyBase.FormClosing
   Try
      twnSession.Shutdown()
   Catch ex As Exception
      MessageBox.Show(ex.Message)
   End Try
End Sub

[C#]


private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
   try
   {
      twnSession.Shutdown();
   }
   catch (Exception ex)
   {
      MessageBox.Show(this, ex.Message);
   }
}

Add an event handler to the buttonSelectSource Click event and code it as follows:

[Visual Basic]

 
Private Sub buttonSelectSource_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles buttonSelectSource.Click
   Try
      twnSession.SelectSource(String.Empty)
   Catch ex As Exception
      MessageBox.Show(ex.Message)
   End Try
End Sub

[C#]


private void buttonSelectSource_Click(object sender, System.EventArgs e)
{
   try
   {
      twnSession.SelectSource(string.Empty);
   }
   catch (Exception ex)
   {
      MessageBox.Show(this, ex.Message);
   }
}

Add an event handler to the buttonUseCapability Click event and code it as follows:

[Visual Basic]


Private Sub buttonUseCapability_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles buttonUseCapability.Click
   Try
      Dim twGetCapability As TwainCapability = twnSession.GetCapability(TwainCapabilityType.ImageTransferMechanism, TwainGetCapabilityMode.GetCurrent)
      
      If twGetCapability.Information.ContainerType = TwainContainerType.OneValue Then
         Dim capValue As TwainCapabilityValue = twGetCapability.OneValueCapability.Value
         
         If capValue <> TwainCapabilityValue.TransferMechanismFile Then
            Dim twSetCapability As TwainCapability
            
            twSetCapability = new TwainCapability
            twSetCapability.Information.ContainerType = TwainContainerType.OneValue
            twSetCapability.Information.Type = TwainCapabilityType.ImageTransferMechanism
            
            twSetCapability.OneValueCapability.ItemType = TwainItemType.Uint16
            twSetCapability.OneValueCapability.Value = TwainCapabilityValue.TransferMechanismFile
            
            twnSession.SetCapability(twSetCapability, TwainSetCapabilityMode.Set)
         End If
      End If
   Catch ex As Exception
      MessageBox.Show(ex.Message)
   End Try
End Sub

[C#]

 
private void buttonUseCapability_Click(object sender, System.EventArgs e)
{
   try
   {
      TwainCapability twGetCapability = twnSession.GetCapability(TwainCapabilityType.ImageTransferMechanism, TwainGetCapabilityMode.GetCurrent);
      
      if (twGetCapability.Information.ContainerType == TwainContainerType.OneValue)
      {
         TwainCapabilityValue capValue = (TwainCapabilityValue)twGetCapability.OneValueCapability.Value;
         
         if (capValue != TwainCapabilityValue.TransferMechanismFile)
         {
            TwainCapability twSetCapability;
            
            twSetCapability = new TwainCapability();
            twSetCapability.Information.ContainerType = TwainContainerType.OneValue;
            twSetCapability.Information.Type = TwainCapabilityType.ImageTransferMechanism;
            
            twSetCapability.OneValueCapability.ItemType = TwainItemType.Uint16;
            twSetCapability.OneValueCapability.Value = TwainCapabilityValue.TransferMechanismFile;
            
            twnSession.SetCapability(twSetCapability, TwainSetCapabilityMode.Set);
         }
      }
   }
   catch (Exception ex)
   {
      MessageBox.Show(this, ex.Message);
   }
}

Add an event handler to the buttonSetBrightness Click event and code it as follows:

[Visual Basic]

 
Private Sub buttonSetBrightness_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles buttonSetBrightness.Click
   Try
      Dim twCapability As TwainCapability = new TwainCapability
      
      twCapability.Information.ContainerType = TwainContainerType.OneValue
      twCapability.Information.Type = TwainCapabilityType.ImageBrightness
      
      Dim brightnessValue As Integer = 50
      twCapability.OneValueCapability.ItemType = TwainItemType.Fix32
      twCapability.OneValueCapability.Value = brightnessValue
      
      twnSession.SetCapability(twCapability, TwainSetCapabilityMode.Set)
   Catch ex As Exception
      MessageBox.Show(ex.Message)
   End Try
End Sub

[C#]

 
private void buttonSetBrightness_Click(object sender, System.EventArgs e)
{
   try
   {
      TwainCapability twCapability = new TwainCapability();
      
      twCapability.Information.ContainerType = TwainContainerType.OneValue;
      twCapability.Information.Type = TwainCapabilityType.ImageBrightness;
      
      float brightnessValue = 50;
      twCapability.OneValueCapability.ItemType = TwainItemType.Fix32;
      twCapability.OneValueCapability.Value = brightnessValue;
      
      twnSession.SetCapability(twCapability, TwainSetCapabilityMode.Set);
   }
   catch (Exception ex)
   {
      MessageBox.Show(this, ex.Message);
   }
}

Add an event handler to the buttonAcquire Click event and code it as follows:

[Visual Basic]

 
Private Sub buttonAcquire_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles buttonAcquire.Click
   Try
      Dim twnPros As TwainProperties = twnSession.Properties
      Dim dataTransfer As TwainDataTransferProperties = twnPros.DataTransfer
      dataTransfer.FileName = "C:\Users\Public\Documents\LEADTOOLS Images\Twain.bmp"
      twnPros.DataTransfer = dataTransfer
      twnSession.Properties = twnPros
      twnSession.Acquire(TwainUserInterfaceFlags.Show)
   Catch ex As Exception
      MessageBox.Show(ex.Message)
   End Try
End Sub

[C#]

 
private void buttonAcquire_Click(object sender, System.EventArgs e)
{
   try
   {
      TwainProperties twnPros = twnSession.Properties;
      TwainDataTransferProperties dataTransfer = twnPros.DataTransfer;
      dataTransfer.FileName = @"C:\Users\Public\Documents\LEADTOOLS Images\Twain.bmp";
      twnPros.DataTransfer = dataTransfer;
      twnSession.Properties = twnPros;
      twnSession.Acquire(TwainUserInterfaceFlags.Show);
   }
   catch (Exception ex)
   {
      MessageBox.Show(ex.Message);
   }
}

Build, and Run the program to test it.

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Get Twain Capability