EnumItemsEvent Event

Summary

Occurs for each found WIA child item after calling the EnumChildItems method.

Syntax

C++/CLI

Python

public event EventHandler<WiaEnumItemsEventArgs> EnumItemsEvent

public: 
event EventHandler<WiaEnumItemsEventArgs^>^ EnumItemsEvent

def EnumItemsEvent(sender,e): # sender: WiaSession e: WiaEnumItemsEventArgs

Event Data

The event handler receives an argument of type WiaEnumItemsEventArgs containing data related to this event. The following WiaEnumItemsEventArgs properties provide information specific to this event.

Property	Description
Item	Gets the enumerated item.
ItemsCount	Gets the count of the items being enumerated.
Stop	Enables or disables firing the EnumItemsEvent event.

Remarks

This event will be called while enumerating the WIA child items for the parent item passed through the call to the EnumChildItems method to provide the user with a handle for each found child item and also gives the ability to abort the enumeration process.

Example

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.Wia; 
 
 
WiaSession wiaSession; 
       
public void GetRootItemExample(IntPtr parent) 
{ 
   if (!WiaSession.IsAvailable(WiaVersion.Version1)) 
   { 
      Console.WriteLine("WIA version 1.0 not installed."); 
      return; 
   } 
   wiaSession = new WiaSession(); 
   wiaSession.Startup(WiaVersion.Version1); 
 
   DialogResult res = wiaSession.SelectDeviceDlg(parent, WiaDeviceType.Default, WiaSelectSourceFlags.NoDefault); 
   if (res != DialogResult.OK) 
   { 
      Console.WriteLine("Error selecting WIA device."); 
      wiaSession.Shutdown(); 
      return; 
   } 
 
   object rootItem = wiaSession.GetRootItem(null); 
   if (rootItem != null) 
   { 
      wiaSession.EnumItemsEvent += new EventHandler<WiaEnumItemsEventArgs>(wiaSession_EnumItemsEvent); 
 
      wiaSession.EnumChildItems(rootItem); 
 
      wiaSession.EnumItemsEvent -= new EventHandler<WiaEnumItemsEventArgs>(wiaSession_EnumItemsEvent); 
   } 
 
   wiaSession.Shutdown(); 
} 
 
void wiaSession_EnumItemsEvent(object sender, WiaEnumItemsEventArgs e) 
{ 
   if (e.Item != null) 
   { 
      WiaDataTransferProperties dataTransfer = WiaDataTransferProperties.Empty; 
      WiaImageEffectsProperties imageEffects = WiaImageEffectsProperties.Empty; 
 
      WiaProperties properties = wiaSession.GetProperties(e.Item); 
 
      dataTransfer.ImageDataType = WiaImageDataType.Grayscale; 
      imageEffects.Brightness = 250; 
 
      properties.DataTransfer = dataTransfer; 
      properties.ImageEffects = imageEffects; 
      properties.ScanningMode = WiaScanningModeFlags.Feeder;   // set scanning source to Feeder 
      properties.MaximumNumberOfPages = 0;                     // scan all pages in feeder 
      properties.ImageType = WiaImageType.Grayscale; 
      properties.Orientation = WiaOrientation.Portrait; 
 
      WiaImageResolutionProperties imageResolution = properties.ImageResolution; 
      imageResolution.BitsPerPixel = 8; 
      imageResolution.HorizontalResolution = 600; 
      imageResolution.VerticalResolution = 600; 
      properties.ImageResolution = imageResolution; 
 
      wiaSession.SetPropertiesEvent += new EventHandler<WiaSetPropertiesEventArgs>(wiaSession_SetPropertiesEvent); 
 
      wiaSession.SetProperties(e.Item, properties); 
 
      wiaSession.SetPropertiesEvent -= new EventHandler<WiaSetPropertiesEventArgs>(wiaSession_SetPropertiesEvent); 
 
      wiaSession.FreeItem(e.Item); 
   } 
} 
 
void wiaSession_SetPropertiesEvent(object sender, WiaSetPropertiesEventArgs e) 
{ 
   if (e.Error <= 0) 
   { 
      Console.WriteLine("Failed to set the below property:\n\tProperty Id: {0}\n\tProperty Value: {1}\n\tError: {2}\n\n", e.PropertyId.ToString(), e.Value.ToString(), e.Error.ToString()); 
   } 
}