/// <summary>
/// Sets value of SANE device option.
/// </summary>
public void SetValueOfSaneDeviceOption()
{
    // create SANE device manager
    using (Vintasoft.Sane.SaneLocalDeviceManager deviceManager = new Vintasoft.Sane.SaneLocalDeviceManager())
    {
        // open SANE device manager
        deviceManager.Open();

        // get count of SANE devices
        int deviceCount = deviceManager.Devices.Count;
        if (deviceCount == 0)
        {
            System.Console.WriteLine("Devices are not found.");
            return;
        }

        // select the first SANE device
        Vintasoft.Sane.SaneLocalDevice device = deviceManager.Devices[0];

        // open SANE device
        device.Open();

        System.Console.WriteLine("Device name: " + device.Name);

        // get SANE device option with name "source"
        Vintasoft.Sane.SaneLocalDeviceOption sourceOption = device.Options.Find("source");
        // if option is found
        if (sourceOption != null)
        {
            // set new value for option
            sourceOption.SetValue("Flatbed");
        }

        // close SANE device
        device.Close();

        // close SANE device manager
        deviceManager.Close();
    }

    System.Console.ReadLine();
}

''' <summary>
''' Sets value of SANE device option.
''' </summary>
Public Sub SetValueOfSaneDeviceOption()
        ' create SANE device manager
        Using deviceManager As New Vintasoft.Sane.SaneLocalDeviceManager()
                ' open SANE device manager
                deviceManager.Open()

                ' get count of SANE devices
                Dim deviceCount As Integer = deviceManager.Devices.Count
                If deviceCount = 0 Then
                        System.Console.WriteLine("Devices are not found.")
                        Return
                End If

                ' select the first SANE device
                Dim device As Vintasoft.Sane.SaneLocalDevice = deviceManager.Devices(0)

                ' open SANE device
                device.Open()

                System.Console.WriteLine("Device name: " + device.Name)

                ' get SANE device option with name "source"
                Dim sourceOption As Vintasoft.Sane.SaneLocalDeviceOption = device.Options.Find("source")
                ' if option is found
                If sourceOption IsNot Nothing Then
                        ' set new value for option
                        sourceOption.SetValue("Flatbed")
                End If

                ' close SANE device
                device.Close()

                ' close SANE device manager
                deviceManager.Close()
        End Using

        System.Console.ReadLine()
End Sub