Get a Fast Twain Scan from a Scanner

Take the following steps to start a project and to add some code to find the fastest configuration for your scanner using the LEADTOOLS Fast TWAIN feature:

Start Visual Studio.
Choose File->New->Project… from the menu.
In the New Project dialog box, choose either "Visual C# Projects" or "VB Projects" in the Projects Type List, and choose "Windows Application" in the Templates List.
Type the project name as "GetFastTwainScan" 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 3 instances of Button control to the top of the form and set the following properties for them:

Text	Name
Select Source	buttonSelectSource
Find Fast Config	buttonFindFastConfig
Acquire Fast Config	buttonAcquireFastConfig

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:

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

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

Declare the following private variable:

Private WithEvents twnSession As TwainSession 
Private fastConfigResult As TwainFindFastConfigurationResult

private TwainSession twnSession; 
private TwainFindFastConfigurationResult fastConfigResult;

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

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. 
      Dim MY_LICENSE_FILE As String = "d:\temp\TestLic.lic" 
      Dim MY_DEVELOPER_KEY As String = "xyz123abc" 
      RasterSupport.SetLicense(MY_LICENSE_FILE, MY_DEVELOPER_KEY) 
      twnSession = new TwainSession 
      twnSession.Startup(Me.Handle, "manufacturer", "productFamily", "version", "application", TwainStartupFlags.None) 
   Catch ex As Exception 
      MessageBox.Show(ex.Message) 
   End Try 
End Sub

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. 
      string MY_LICENSE_FILE = "d:\\temp\\TestLic.lic"; 
      string MY_DEVELOPER_KEY = "xyz123abc"; 
      RasterSupport.SetLicense(MY_LICENSE_FILE, MY_DEVELOPER_KEY); 
      twnSession = new TwainSession(); 
      twnSession.Startup(this.Handle, "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:

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

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:

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

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 buttonFindFastConfig Click event and code it as follows:

Private Sub buttonFindFastConfig_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles buttonFindFastConfig.Click 
   Try 
      twnSession.EnableFastConfigurationEvent = False 
      fastConfigResult = twnSession.FindFastConfiguration("C:\Users\Public\Documents\LEADTOOLS Images", TwainFastUserInterfaceFlags.Show Or TwainFastUserInterfaceFlags.UseThread, 8, 5, Nothing) 
   Catch ex As Exception 
      MessageBox.Show(ex.Message) 
   End Try 
End Sub

private void buttonFindFastConfig_Click(object sender, System.EventArgs e) 
{ 
   try 
   { 
      twnSession.EnableFastConfigurationEvent = false; 
      fastConfigResult = twnSession.FindFastConfiguration(@"C:\Users\Public\Documents\LEADTOOLS Images", TwainFastUserInterfaceFlags.Show |   TwainFastUserInterfaceFlags.UseThread, 8, 5, null); 
   } 
   catch (Exception ex) 
   { 
      MessageBox.Show(this, ex.Message); 
   } 
}

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

Private Sub buttonAcquireFastConfig_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles buttonAcquireFastConfig.Click 
   Try 
      twnSession.EnableAcquireMultiPageEvent = False 
      twnSession.AcquireFast("C:\Users\Public\Documents\LEADTOOLS Images\test", _ 
                             TwainFastUserInterfaceFlags.Show, _ 
                             fastConfigResult.Best.TransferMechanism, _ 
                             fastConfigResult.Best.ImageFormat, _ 
                             fastConfigResult.Best.BitsPerPixel, _ 
                             True, _ 
                             fastConfigResult.Best.BufferSize, _ 
                             True) 
   Catch ex As Exception 
      MessageBox.Show(ex.Message) 
   End Try 
End Sub

private void buttonAcquireFastConfig_Click(object sender, System.EventArgs e) 
{ 
   try 
   { 
      twnSession.EnableAcquireMultiPageEvent = false; 
      twnSession.AcquireFast(@"C:\Users\Public\Documents\LEADTOOLS Images\test", 
           TwainFastUserInterfaceFlags.Show, 
           fastConfigResult.Best.TransferMechanism, 
           fastConfigResult.Best.ImageFormat, 
           fastConfigResult.Best.BitsPerPixel, 
           true, 
           fastConfigResult.Best.BufferSize, 
           true); 
   } 
   catch (Exception ex) 
   { 
      MessageBox.Show(this, ex.Message); 
   } 
}

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Help Version 20.0.2020.4.3