VintaSoft Twain .NET SDK 15.3: Руководство для .NET разработчика
Vintasoft.WiaImageScanning Namespace / WiaDevice Class / AcquireImageSync() Method
Синтаксис Exceptions Ремарки Example Требования Смотрите также
В этом разделе
    AcquireImageSync() Метод (WiaDevice)
    В этом разделе
    Синхронно получает одно изображение в формате RAW с этого устройства WIA.
    Синтаксис
    'Declaration
    
    Public Function AcquireImageSync() As WiaAcquiredImage
    
    
    public WiaAcquiredImage AcquireImageSync()
    
    
    public: WiaAcquiredImage* AcquireImageSync()
    
    
    public:
    WiaAcquiredImage^ AcquireImageSync()

    Return Value

    Текущее состояние процесса получения изображения.
    Исключения
    ИсключениеОписание
    Выбрасывается, если устройство не открыто ИЛИ другой процесс сканирования изображений уже работает.
    Ремарки

    Этот метод необходимо вызывать в цикле до тех пор, пока метод не вернет null, т. е. больше нет изображений для сканирования.

    Пример

    Вот C#/VB.NET код, который демонстрирует, как синхронно получить изображения с устройства WIA.

    
    ''' <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
    
    
    
    /// <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();
    }
    
    

    Требования

    Целевые платформы: .NET 9; .NET 8; .NET 7; .NET 6; .NET Framework 4.8, 4.7, 4.6, 4.5, 4.0, 3.5

    Смотрите также