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GetItem Method

Summary

Gets the specified extended image information item.

Syntax

C++

public object GetItem( 
   int index, 
   int barcodeTextIndex 
)

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

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.

Remarks

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 AcquirePage event.

Example

using Leadtools; 
using Leadtools.Twain; 
 
public void GetItemExample(IntPtr 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); 
   } 
}

Imports Leadtools 
Imports Leadtools.Twain 
 
Public Sub GetItemExample(ByVal parent As IntPtr) 
   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

Requirements

Target Platforms

Reference

TwainInformation Class

TwainInformation Members

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Help Version 20.0.2020.3.31

Leadtools.Twain Assembly

Introduction

Getting Started

Namespaces

Leadtools.Twain Namespace

Assemblies