DeviceManager Class

Visual Basic
C#
Managed Extensions for C++
C++/CLI

'Declaration
 
<ToolboxBitmapAttribute(Vintasoft.Twain.DeviceManager, "DeviceManager.icon.bmp")>
<DesignerCategoryAttribute("Component")>
Public NotInheritable Class DeviceManager 
   Inherits System.ComponentModel.Component

'Usage
 
Dim instance As DeviceManager

[ToolboxBitmap(Vintasoft.Twain.DeviceManager, "DeviceManager.icon.bmp")]
[DesignerCategory("Component")]
public sealed class DeviceManager : System.ComponentModel.Component

[ToolboxBitmap(Vintasoft.Twain.DeviceManager, "DeviceManager.icon.bmp")]
[DesignerCategory("Component")]
public __gc __sealed class DeviceManager : public System.ComponentModel.Component

[ToolboxBitmap(Vintasoft.Twain.DeviceManager, "DeviceManager.icon.bmp")]
[DesignerCategory("Component")]
public ref class DeviceManager sealed : public System.ComponentModel.Component

Class allows to:

determine that TWAIN is installed in the system
choose which TWAIN device manager to use (1.x or 2.x)
specify path to TWAIN device manager
get number of TWAIN devices installed in the system
select the device
get access to object that manipulates TWAIN device

This example shows how to select the device and acquire images from the device.

VB.NET

''' <summary>
''' Starts the asynchronous image acquisition from scanner.
''' </summary>
Private Sub StartScan(ByVal deviceManager As Vintasoft.Twain.DeviceManager)
    ' specify TWAIN name of this application
    deviceManager.ApplicationProductName = "MyTwainApplication"
    Try
        ' open the device manager
        deviceManager.Open()
            
        ' show the default device selection dialog
        If Not deviceManager.ShowDefaultDeviceSelectionDialog() Then
            ' exit if default device is not selected
            Return
        End If
            
        ' get reference to the default device
        Dim device As Vintasoft.Twain.Device = deviceManager.DefaultDevice
        ' acquire image(s) from the device
        device.Acquire()
    Catch ex As Vintasoft.Twain.TwainException
        Console.WriteLine(ex.Message)
    End Try
End Sub

C#

/// <summary>
/// Starts the asynchronous image acquisition from scanner.
/// </summary>
void StartScan(Vintasoft.Twain.DeviceManager deviceManager)
{
    // specify TWAIN name of this application
    deviceManager.ApplicationProductName = "MyTwainApplication";
    try
    {
        // open the device manager
        deviceManager.Open();
            
        // show the default device selection dialog
        if (!deviceManager.ShowDefaultDeviceSelectionDialog())
            // exit if default device is not selected
            return;
            
        // get reference to the default device
        Vintasoft.Twain.Device device = deviceManager.DefaultDevice;
        // acquire image(s) from the device
        device.Acquire();
    }
    catch (Vintasoft.Twain.TwainException ex)
    {
        System.Console.WriteLine(ex.Message);
    }
}

System.Object
   System.MarshalByRefObject
      System.ComponentModel.Component
         Vintasoft.Twain.DeviceManager

Target Platforms: .NET 6; .NET 5; .NET Core 3.1; .NET Framework 4.8, 4.7, 4.6, 4.5, 4.0, 3.5

Reference

DeviceManager Members
Vintasoft.Twain Namespace