Class SyncScan_StopFeeder

    ''' <summary>
    ''' This method scans the first image, stops the document feeder,
    ''' scans the second image.
    ''' </summary>
    Public Shared Sub ScanImage_StopFeeder_ScanImage()
        Dim imageCount As Integer = 0

        ' create the device manager
        Using deviceManager As New Vintasoft.Twain.DeviceManager()
            deviceManager.IsTwain2Compatible = True
            ' open the device manager
            deviceManager.Open()

            ' get the device
            Dim deviceName As String = "KODAK Scanner: i5000"
            Dim device As Vintasoft.Twain.Device = deviceManager.Devices.Find(deviceName)
            If device Is Nothing Then
                Throw New ApplicationException(String.Format("Device '{0}' is not found.", deviceName))
            End If

            ' disable device UI
            device.ShowUI = False
            ' specify that device must be closed after scan
            device.DisableAfterAcquire = True

            ' open the device
            device.Open()
            ' specify that 2 images must be acquired from scanner
            device.XferCount = 2

            ' run synchronous image acquisition
            Dim acquireModalState1 As Vintasoft.Twain.AcquireModalState = Vintasoft.Twain.AcquireModalState.None
            Do
                acquireModalState1 = device.AcquireModal()
                Select Case acquireModalState1
                    Case Vintasoft.Twain.AcquireModalState.ImageAcquired
                        Console.WriteLine("Image is acquired.")
                        If device.AcquiredImage IsNot Nothing Then
                            device.AcquiredImage.Dispose()
                        End If

                        imageCount += 1

                        ' stop the feeder
                        device.StopFeeder()
                        Exit Select

                    Case Vintasoft.Twain.AcquireModalState.ScanCompleted
                        Console.WriteLine("Scan is completed.")
                        Exit Select

                    Case Vintasoft.Twain.AcquireModalState.ScanCanceled
                        Console.WriteLine("Scan is canceled.")
                        Exit Select

                    Case Vintasoft.Twain.AcquireModalState.ScanFailed
                        Console.WriteLine(String.Format("Scan is failed: {0}.", device.ErrorString))
                        Exit Select
                End Select
            Loop While acquireModalState1 <> Vintasoft.Twain.AcquireModalState.None

            If imageCount <> 1 Then
                Throw New ApplicationException("Wrong acquired image count.")
            End If

            If device.State <> Vintasoft.Twain.DeviceState.TransferReady Then
                Throw New ApplicationException("Feeder is NOT stopped.")
            End If
            Console.WriteLine("Feeder is stopped.")

            ' continue asynchronous image acquisition
            Do
                acquireModalState1 = device.AcquireModal()
                Select Case acquireModalState1
                    Case Vintasoft.Twain.AcquireModalState.ImageAcquired
                        Console.WriteLine("Image is acquired.")

                        If device.AcquiredImage IsNot Nothing Then
                            device.AcquiredImage.Dispose()
                        End If

                        imageCount = imageCount + 1
                        Exit Select

                    Case Vintasoft.Twain.AcquireModalState.ScanCompleted
                        Console.WriteLine("Scan is completed.")
                        Exit Select

                    Case Vintasoft.Twain.AcquireModalState.ScanCanceled
                        Console.WriteLine("Scan is canceled.")
                        Exit Select

                    Case Vintasoft.Twain.AcquireModalState.ScanFailed
                        Console.WriteLine(String.Format("Scan is failed: {0}.", device.ErrorString))
                        Exit Select
                End Select
            Loop While acquireModalState1 <> Vintasoft.Twain.AcquireModalState.None

            If imageCount <> 2 Then
                Throw New ApplicationException("Wrong acquired image count.")
            End If

            ' close the device
            device.Close()
        End Using
    End Sub

End Class

namespace TwainExamples_CSharp
{
    class SyncScan_StopFeeder
    {

        /// <summary>
        /// This method scans the first image, stops the document feeder,
        /// scans the second image.
        /// </summary>
        public static void ScanImage_StopFeeder_ScanImage()
        {
            int imageCount = 0;

            // create the device manager
            using (Vintasoft.Twain.DeviceManager deviceManager = new Vintasoft.Twain.DeviceManager())
            {
                deviceManager.IsTwain2Compatible = true;
                // open the device manager
                deviceManager.Open();

                // get the device
                string deviceName = "KODAK Scanner: i5000";
                Vintasoft.Twain.Device device = deviceManager.Devices.Find(deviceName);
                if (device == null)
                    throw new System.ApplicationException(string.Format("Device '{0}' is not found.", deviceName));

                // disable device UI
                device.ShowUI = false;
                // specify that device must be closed after scan
                device.DisableAfterAcquire = true;

                // open the device
                device.Open();
                // specify that 2 images must be acquired from scanner
                device.XferCount = 2;

                // run asynchronous image acquisition
                Vintasoft.Twain.AcquireModalState acquireModalState = Vintasoft.Twain.AcquireModalState.None;
                do
                {
                    acquireModalState = device.AcquireModal();
                    switch (acquireModalState)
                    {
                        case Vintasoft.Twain.AcquireModalState.ImageAcquired:
                            System.Console.WriteLine("Image is acquired.");
                            if (device.AcquiredImage != null)
                                device.AcquiredImage.Dispose();

                            imageCount++;

                            // stop the feeder
                            device.StopFeeder();
                            break;

                        case Vintasoft.Twain.AcquireModalState.ScanCompleted:
                            System.Console.WriteLine("Scan is completed.");
                            break;

                        case Vintasoft.Twain.AcquireModalState.ScanCanceled:
                            System.Console.WriteLine("Scan is canceled.");
                            break;

                        case Vintasoft.Twain.AcquireModalState.ScanFailed:
                            System.Console.WriteLine(string.Format("Scan is failed: {0}.", device.ErrorString));
                            break;
                    }
                }
                while (acquireModalState != Vintasoft.Twain.AcquireModalState.None);

                if (imageCount != 1)
                    throw new System.ApplicationException("Wrong acquired image count.");

                if (device.State != Vintasoft.Twain.DeviceState.TransferReady)
                    throw new System.ApplicationException("Feeder is NOT stopped.");
                System.Console.WriteLine("Feeder is stopped.");

                // continue asynchronous image acquisition
                do
                {
                    acquireModalState = device.AcquireModal();
                    switch (acquireModalState)
                    {
                        case Vintasoft.Twain.AcquireModalState.ImageAcquired:
                            System.Console.WriteLine("Image is acquired.");

                            if (device.AcquiredImage != null)
                                device.AcquiredImage.Dispose();

                            imageCount++;
                            break;

                        case Vintasoft.Twain.AcquireModalState.ScanCompleted:
                            System.Console.WriteLine("Scan is completed.");
                            break;

                        case Vintasoft.Twain.AcquireModalState.ScanCanceled:
                            System.Console.WriteLine("Scan is canceled.");
                            break;

                        case Vintasoft.Twain.AcquireModalState.ScanFailed:
                            System.Console.WriteLine(string.Format("Scan is failed: {0}.", device.ErrorString));
                            break;
                    }
                }
                while (acquireModalState != Vintasoft.Twain.AcquireModalState.None);

                if (imageCount != 2)
                    throw new System.ApplicationException("Wrong acquired image count.");

                // close the device
                device.Close();
            }
        }

    }
}