VintaSoft Twain .NET SDK 15.0: Documentation for .NET developer
In This Topic
    Cancel image acquisition from SANE scanner
    In This Topic
    You should call the SaneLocalDevice.CancelImageTransfer method if you want to cancel the image acquisition from SANE scanner.

    Here is an example that demonstrates how to cancel the current synchronous image transfer from SANE scanner:
    /// <summary>
    /// Acquires one image from SANE device and cancels image transfer.
    /// </summary>
    public static void AcquireOneImageFromSaneDeviceAndCancelScan()
    {
        // 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();
    
            Vintasoft.Sane.SaneAcquiredImage acquiredImage;
            do
            {
                try
                {
                    // acquire image from SANE device
                    acquiredImage = device.AcquireImageSync();
                    // if image is received
                    if (acquiredImage != null)
                    {
                        System.Console.WriteLine("Image is acquired.");
    
                        // cancel image transfer
                        device.CancelImageTransfer();
                    }
                    // if image is not received
                    else
                    {
                        System.Console.WriteLine("Scan is completed.");
                        break;
                    }
                }
                catch (System.Exception ex)
                {
                    System.Console.WriteLine(string.Format("Scan is failed: {0}", ex.Message));
                    break;
                }
            }
            // while device has more images to scan
            while (device.HasMoreImagesToScan);
    
            // close SANE device
            device.Close();
    
            // close SANE device manager
            deviceManager.Close();
        }
    
        System.Console.ReadLine();
    }
    
    ''' <summary>
    ''' Acquires one image from SANE device and cancels image transfer.
    ''' </summary>
    Public Shared Sub AcquireOneImageFromSaneDeviceAndCancelScan()
            ' 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()
    
                    Dim acquiredImage As Vintasoft.Sane.SaneAcquiredImage
                    Do
                            Try
                                    ' acquire image from SANE device
                                    acquiredImage = device.AcquireImageSync()
                                    ' if image is received
                                    If acquiredImage IsNot Nothing Then
                                            System.Console.WriteLine("Image is acquired.")
    
                                            ' cancel image transfer
                                            device.CancelImageTransfer()
                                    Else
                                            ' if image is not received
                                            System.Console.WriteLine("Scan is completed.")
                                            Exit Try
                                    End If
                            Catch ex As System.Exception
                                    System.Console.WriteLine(String.Format("Scan is failed: {0}", ex.Message))
                                    Exit Try
                            End Try
                    ' while device has more images to scan
                    Loop While device.HasMoreImagesToScan
    
                    ' close SANE device
                    device.Close()
    
                    ' close SANE device manager
                    deviceManager.Close()
            End Using
    
            System.Console.ReadLine()
    End Sub