VintaSoft Twain .NET SDK 15.2: Руководство для .NET разработчика
Vintasoft.EsclImageScanning Namespace / EsclDevice Class / AcquireImageSyncAsFileStream Methods / AcquireImageSyncAsFileStream(EsclScanDocumentFormat) Method
Синтаксис Exceptions Example Требования Смотрите также
В этом разделе
    AcquireImageSyncAsFileStream(EsclScanDocumentFormat) Метод (EsclDevice)
    В этом разделе
    Синхронно получает одно изображение в виде байтового массива с этого устройства eSCL.
    Синтаксис
    'Declaration
    
    Public Overloads Function AcquireImageSyncAsFileStream( _
    ByVal scanDocumentFormat
    Формат документа сканирования, определяющий формат
    As EsclScanDocumentFormat _
    ) As Byte[]
    public byte[] AcquireImageSyncAsFileStream(
    EsclScanDocumentFormat scanDocumentFormat
    )
    public: byte[] AcquireImageSyncAsFileStream(
    EsclScanDocumentFormat scanDocumentFormat
    )
    public:
    byte[] AcquireImageSyncAsFileStream(
    EsclScanDocumentFormat scanDocumentFormat
    )

    Parameters

    scanDocumentFormat
    Формат документа сканирования, определяющий формат

    Return Value

    Массив байтов, содержащий данные отсканированного изображения.
    Исключения
    ИсключениеОписание
    Выбрасывается, если устройство не открыто ИЛИ текущее задание сканирования не найдено.
    Пример

    Вот C#/VB.NET код, который демонстрирует, как синхронно получить изображения в виде JPEG-потока с устройства eSCL.

    
    ''' <summary>
    ''' Synchronously acquire images as JPEG stream from eSCL device.
    ''' </summary>
    Public Sub SynchronouslyAcquireImagesAsJpegStreamFromEsclDevice()
        ' create eSCL device manager
        Using deviceManager As New Vintasoft.EsclImageScanning.EsclDeviceManager()
            ' open eSCL device manager
            deviceManager.Open()
    
            ' wait while the eSCL device manager searches for eSCL devices
            System.Threading.Thread.Sleep(deviceManager.DeviceSearchTimeout)
            ' get count of eSCL 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 eSCL device
            Dim device As Vintasoft.EsclImageScanning.EsclDevice = deviceManager.Devices(0)
    
            ' open eSCL device
            device.Open()
    
            Dim imageIndex As Integer = 0
            Dim acquiredImageBytes As Byte() = Nothing
            Do
                Try
                    ' acquire image as JPEG stream from eSCL device
                    acquiredImageBytes = device.AcquireImageSyncAsFileStream(Vintasoft.EsclImageScanning.EsclScanDocumentFormat.JPEG)
                    ' if image is received
                    If acquiredImageBytes IsNot Nothing Then
                        imageIndex += 1
                        Dim filename As String = String.Format("scannedImage-{0}.jpg", imageIndex)
                        If System.IO.File.Exists(filename) Then
                            System.IO.File.Delete(filename)
                        End If
    
                        System.IO.File.WriteAllBytes(filename, acquiredImageBytes)
    
                        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 acquiredImageBytes IsNot Nothing
    
            ' close eSCL device
            device.Close()
    
            ' close eSCL device manager
            deviceManager.Close()
        End Using
    
        System.Console.ReadLine()
    End Sub
    
    
    
    /// <summary>
    /// Synchronously acquire images as JPEG stream from eSCL device.
    /// </summary>
    public void SynchronouslyAcquireImagesAsJpegStreamFromEsclDevice()
    {
        // create eSCL device manager
        using (Vintasoft.EsclImageScanning.EsclDeviceManager deviceManager = new Vintasoft.EsclImageScanning.EsclDeviceManager())
        {
            // open eSCL device manager
            deviceManager.Open();
    
            // wait while the eSCL device manager searches for eSCL devices
            System.Threading.Thread.Sleep(deviceManager.DeviceSearchTimeout);
            // get count of eSCL devices
            int deviceCount = deviceManager.Devices.Count;
            if (deviceCount == 0)
            {
                System.Console.WriteLine("Devices are not found.");
                return;
            }
    
            // select the first eSCL device
            Vintasoft.EsclImageScanning.EsclDevice device = deviceManager.Devices[0];
    
            // open eSCL device
            device.Open();
    
            int imageIndex = 0;
            byte[] acquiredImageBytes = null;
            do
            {
                try
                {
                    // acquire image as JPEG stream from eSCL device
                    acquiredImageBytes = device.AcquireImageSyncAsFileStream(Vintasoft.EsclImageScanning.EsclScanDocumentFormat.JPEG);
                    // if image is received
                    if (acquiredImageBytes != null)
                    {
                        imageIndex++;
                        string filename = string.Format("scannedImage-{0}.jpg", imageIndex);
                        if (System.IO.File.Exists(filename))
                            System.IO.File.Delete(filename);
    
                        System.IO.File.WriteAllBytes(filename, acquiredImageBytes);
    
                        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 (acquiredImageBytes != null);
    
            // close eSCL device
            device.Close();
    
            // close eSCL device manager
            deviceManager.Close();
        }
    
        System.Console.ReadLine();
    }
    
    

    Требования

    Целевые платформы: .NET 9; .NET 8; .NET 7; .NET 6; .NET Framework 4.8, 4.7, 4.6, 4.5

    Смотрите также