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 "<LEADTOOLS_INSTALLDIR>\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 4 instances 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

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.SetLicense(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.SetLicense(RasterSupportType.Document, "TestKey");
                  twnSession = new TwainSession();
                  twnSession.Startup(this, "manufacturer", "productFamily", "version", "application", 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.