How to get value of TWAIN device capability?

In This Topic

Here is an example that demonstrates how to use properties and methods of TWAIN capability for getting information about pixel types supported by TWAIN device:

/// <summary>
/// Get information about pixel types supported by device.
/// </summary>
public void GetPixelTypesInfo(Vintasoft.Twain.Device device)
{
    // open the device
    device.Open();

    // get reference to the object that manipulates IPixelType capability
    Vintasoft.Twain.DeviceCapability pixelTypeCap = device.Capabilities.Find(Vintasoft.Twain.DeviceCapabilityId.IPixelType);
    // if the IPixelType capability is supported
    if (pixelTypeCap != null)
    {
        // get information about current, default and supported values of capability

        Vintasoft.Twain.TwainValueContainerBase capValue = pixelTypeCap.GetValue();

        switch (capValue.ContainerType)
        {
            case Vintasoft.Twain.TwainValueContainerType.Enum:
                Vintasoft.Twain.TwainEnumValueContainer capValueAsEnum = (Vintasoft.Twain.TwainEnumValueContainer)capValue;
                System.Array enumValues = capValueAsEnum.EnumValues;

                // output the capability values in human readable format
                System.Console.WriteLine(string.Format("Current pixel type: {0}", enumValues.GetValue(capValueAsEnum.ValueIndex)));
                System.Console.WriteLine(string.Format("Default pixel type: {0}", enumValues.GetValue(capValueAsEnum.DefaultValueIndex)));
                System.Console.Write("Supported pixel types:");
                for (int i = 0; i < enumValues.Length; i++)
                    System.Console.Write(string.Format(" {0}", enumValues.GetValue(i)));
                break;
        }

        System.Console.WriteLine();
    }

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

VB.NET

''' <summary>
''' Get information about pixel types supported by device.
''' </summary>
Public Sub GetPixelTypesInfo(device As Vintasoft.Twain.Device)
        ' open the device
        device.Open()

        ' get reference to the object that manipulates IPixelType capability
        Dim pixelTypeCap As Vintasoft.Twain.DeviceCapability = device.Capabilities.Find(Vintasoft.Twain.DeviceCapabilityId.IPixelType)
        ' if the IPixelType capability is supported
        If pixelTypeCap IsNot Nothing Then
                ' get information about current, default and supported values of capability

                Dim capValue As Vintasoft.Twain.TwainValueContainerBase = pixelTypeCap.GetValue()

                Select Case capValue.ContainerType
                        Case Vintasoft.Twain.TwainValueContainerType.[Enum]
                                Dim capValueAsEnum As Vintasoft.Twain.TwainEnumValueContainer = DirectCast(capValue, Vintasoft.Twain.TwainEnumValueContainer)
                                Dim enumValues As System.Array = capValueAsEnum.EnumValues

                                ' output the capability values in human readable format
                                System.Console.WriteLine(String.Format("Current pixel type: {0}", enumValues.GetValue(capValueAsEnum.ValueIndex)))
                                System.Console.WriteLine(String.Format("Default pixel type: {0}", enumValues.GetValue(capValueAsEnum.DefaultValueIndex)))
                                System.Console.Write("Supported pixel types:")
                                For i As Integer = 0 To enumValues.Length - 1
                                        System.Console.Write(String.Format(" {0}", enumValues.GetValue(i)))
                                Next
                                Exit Select
                End Select

                System.Console.WriteLine()
        End If

        ' close the device
        device.Close()
End Sub

Send Feedback