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Using the Fast Twain Feature
Take the following steps to start a project and to add some code that acquires the images using Fast Twain:
  1. Start Visual Studio .NET.
  2. Choose File->New->Project… from the menu.
  3. 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.
  4. Type the project name as " UsingFastTwainFeature" 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 .
  5. 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 15\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.
  6. Go to the toolbox (View->Toolbox) and Drag and drop a 2 instance of RadioButton control to the top of the form and set the following properties for them:
    Text Name Checked
    Native radioNative False
    Memory radioMemory False
  7. Go to the toolbox (View->Toolbox) and Drag and drop a 1 instance of Button control to the top of the form and set the following properties for them:
    TextName
    Fast AcquirebuttonFastAcquire
  8. Go to the toolbox (View->Toolbox) and Drag and drop a 1 instance of Check Box control to the top of the form and set the following properties for them:
    NameName
    Use Buffer SizecheckBoxUseBufferSize
  9. Go to the toolbox (View->Toolbox) and Drag and drop a 2 instance of Text Box control to the top of the form and change the following properties:
    PropertyValue
    NametextBufferSize
    NametextFileName
  10. 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;
    
  11. Declare the following private variable:

    [Visual Basic]

     
    Private WithEvents twnSession As TwainSession
    
    [C#]
     
    private TwainSession twnSession;
    
  12. 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 14", "LEADTools Twain test sample", TwainStartupFlags.InitializeMultithreaded)
       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.InitializeMultithreaded);
       }
       catch (Exception ex)
       {
          MessageBox.Show(this, ex.Message);
       }
    }
    
  13. 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);
       }
    }
    
  14. Add an event handler to the buttonFastAcquire Click event and code it as follows:

    [Visual Basic]

     
    Private Sub buttonFastAcquire_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles buttonFastAcquire.Click
       Dim transferMode As TwainTransferMode
       Dim transferFormat As RasterImageFormat
    
       If radioMemory.Checked Then
          transferMode = TwainTransferMode.Buffer
          transferFormat = RasterImageFormat.CcittGroup4
       Else
          transferMode = TwainTransferMode.Native
          transferFormat = RasterImageFormat.Tif
       End If
    
       Try
          twnSession.AcquireFast(textFileName.Text, _
                                 TwainFastUserInterfaceFlags.Show Or TwainFastUserInterfaceFlags.UseThread, _
                                 transferMode, _
                                 transferFormat, _
                                 1, _
                                 True, _
                                 Convert.ToInt32(textBufferSize.Text), _
                                 checkBoxUseBufferSize.Checked)
       Catch ex As Exception
          MessageBox.Show(ex.Message)
       End Try
    End Sub
    
    [C#]
     
    private void buttonFastAcquire_Click(object sender, System.EventArgs e)
    {
       TwainTransferMode transferMode;
       RasterImageFormat transferFormat;
    
       if (radioMemory.Checked)
       {
          transferMode = TwainTransferMode.Buffer;
          transferFormat = RasterImageFormat.CcittGroup4;
       }
       else
       {
          transferMode = TwainTransferMode.Native;
          transferFormat = RasterImageFormat.Tif;
       }
    
       try
       {
          twnSession.AcquireFast(textFileName.Text,
                                 TwainFastUserInterfaceFlags.Show | TwainFastUserInterfaceFlags.UseThread,
                                 transferMode,
                                 transferFormat,
                                 1,
                                 true,
                                 Convert.ToInt32(textBufferSize.Text),
                                 checkBoxUseBufferSize.Checked);
       }
       catch (Exception ex)
       {
          MessageBox.Show(ex.Message);
       }
    }
    
  15. Build, and Run the program to test it.