GetItem Method

C#
Visual Basic
Objective-C
Java
C++

public object GetItem( 
   int index,
   int barcodeTextIndex
)

'Declaration
 
Public Function GetItem( _
   ByVal index As Integer, _
   ByVal barcodeTextIndex As Integer _
) As Object

'Usage
 
Dim instance As TwainInformation
Dim index As Integer
Dim barcodeTextIndex As Integer
Dim value As Object
 
value = instance.GetItem(index, barcodeTextIndex)

public:
Object^ GetItem( 
   int index,
   int barcodeTextIndex
)

Parameters

index: Index into the array of extended image information.
barcodeTextIndex: Additional parameter that contains extended image information.
For example when getting barcode text, the barcode text length will be passed in this parameter.

Return Value

The specified extended image information item, cast as an object.
If an error occurs an exception is thrown.

Before calling GetItem, check the value of ReturnCode to ensure the attribue is supported and a value is available.
Possible values are:
TwainReturnCode.Success - Extended Image Information retrieved successfully
TwainReturnCode.InfoNotSupported - Extended Image Information attribute not supported by the device.
TwainReturnCode.DataNotAvailable - Extended Image Information attribute supported, but no value was found (i.e. Would occur if no barcode data were found.)

Extended image information can be Barcode texts, Barcode data, etc.
This method can only be called from within the TwainSession.AcquirePage event.

C#
Visual Basic
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

Copy Code

Imports Leadtools
Imports Leadtools.Twain

Public Sub GetItemExample(ByVal parent As IWin32Window)
   Try
      Dim session As TwainSession = New TwainSession()
      session.Startup(parent, "manufacturer", "productFamily", "version", "application", TwainStartupFlags.None)

      Dim twainExtImageInfo As TwainExtraImageInformation = New TwainExtraImageInformation(1)

      twainExtImageInfo.GetInformation(0).InfoId = TwainExtendedImage.BarcodeText
      twainExtImageInfo.GetInformation(0).ItemType = TwainItemType.Uint32

      session.UpdateExtraImageInformation(twainExtImageInfo)

      If twainExtImageInfo.GetInformation(0).ReturnCode = TwainReturnCode.Success Then
         Dim i As Integer = 0
         Do While i < twainExtImageInfo.GetInformation(0).Count
            Dim item As UInteger = CUInt(twainExtImageInfo.GetInformation(0).GetItem(i, 0))
            'Do more processing on the item value
            i += 1
         Loop
      End If

      session.Shutdown()
   Catch ex As Exception
      MessageBox.Show(ex.Message)
   End Try
End Sub

using Leadtools;
using Leadtools.Twain;

public void GetItemExample(IWin32Window parent)
{
   try
   {
      TwainSession session = new TwainSession();
      session.Startup(parent, "manufacturer", "productFamily", "version", "application", TwainStartupFlags.None);

      TwainExtraImageInformation twainExtImageInfo = new TwainExtraImageInformation(1);

      twainExtImageInfo.GetInformation(0).InfoId = TwainExtendedImage.BarcodeText;
      twainExtImageInfo.GetInformation(0).ItemType = TwainItemType.Uint32;

      session.UpdateExtraImageInformation(twainExtImageInfo);

      if (twainExtImageInfo.GetInformation(0).ReturnCode == TwainReturnCode.Success)
      {
         for (int i=0; i < twainExtImageInfo.GetInformation(0).Count; i++)
         {
            uint item = (uint)twainExtImageInfo.GetInformation(0).GetItem(i, 0);
            //Do more processing on the item value
         }
      }

      session.Shutdown();
   }
   catch (Exception ex)
   {
      MessageBox.Show(ex.Message);
   }
}

Target Platforms

Reference

TwainInformation Class
TwainInformation Members