Синхронное получение изображений со сканера WIA

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VintaSoft Twain .NET SDK позволяет синхронно получать изображения со сканера изображений WIA (в модальном цикле).

Вот шаги, которые необходимо выполнить для синхронного получения изображений с устройства WIA:

Откройте диспетчер устройств WIA.
Откройте устройство WIA.
Задайте параметры сканирования изображений.
Начните синхронное получение изображений от устройства WIA, вызвав метод WiaDevice.AcquireImageSync или WiaDevice.AcquireImageSyncAsFileStream.
Прервите цикл, если метод WiaDevice.AcquireImageSync вернул значение null.

Ниже приведен пример, демонстрирующий, как синхронно получать изображения с устройства WIA и сохранять полученные изображения в документе PDF:

/// <summary>
/// Synchronously acquire images from WIA image scanner.
/// </summary>
public void SynchronouslyAcquireImagesFromWiaDevice()
{
    // create WIA device manager
    using (Vintasoft.WiaImageScanning.WiaDeviceManager deviceManager = new Vintasoft.WiaImageScanning.WiaDeviceManager())
    {
        // open WIA device manager
        deviceManager.Open();

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

        // select the first WIA device
        Vintasoft.WiaImageScanning.WiaDevice device = deviceManager.Devices[0];

        // open WIA device
        device.Open();

        int imageIndex = 0;
        Vintasoft.WiaImageScanning.WiaAcquiredImage acquiredImage = null;
        do
        {
            try
            {
                // acquire image from WIA device
                acquiredImage = device.AcquireImageSync();
                // if image is received
                if (acquiredImage != null)
                {
                    imageIndex++;
                    string filename = string.Format("scannedImage-{0}.png", imageIndex);
                    if (System.IO.File.Exists(filename))
                        System.IO.File.Delete(filename);

                    acquiredImage.Save(filename);

                    System.Console.WriteLine(string.Format("Acquired image is saved to a file '{0}'.", filename));
                }
                // 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 image is acquired
        while (acquiredImage != null);

        // close WIA device
        device.Close();

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

    System.Console.ReadLine();
}

VB.NET

''' <summary>
''' Synchronously acquire images from WIA image scanner.
''' </summary>
Public Sub SynchronouslyAcquireImagesFromWiaDevice()
    ' create WIA device manager
    Using deviceManager As New Vintasoft.WiaImageScanning.WiaDeviceManager()
        ' open WIA device manager
        deviceManager.Open()

        ' get count of WIA 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 WIA device
        Dim device As Vintasoft.WiaImageScanning.WiaDevice = deviceManager.Devices(0)

        ' open WIA device
        device.Open()

        Dim imageIndex As Integer = 0
        Dim acquiredImage As Vintasoft.WiaImageScanning.WiaAcquiredImage = Nothing
        Do
            Try
                ' acquire image from WIA device
                acquiredImage = device.AcquireImageSync()
                ' if image is received
                If acquiredImage IsNot Nothing Then
                    imageIndex += 1
                    Dim filename As String = String.Format("scannedImage-{0}.png", imageIndex)
                    If System.IO.File.Exists(filename) Then
                        System.IO.File.Delete(filename)
                    End If

                    acquiredImage.Save(filename)

                    System.Console.WriteLine(String.Format("Acquired image is saved to a file '{0}'.", filename))
                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 image is acquired
        Loop While acquiredImage IsNot Nothing

        ' close WIA device
        device.Close()

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

    System.Console.ReadLine()
End Sub

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