RasterImagePagesChangedEventArgs Class

Summary

Provides data for the PagesChanged event.

Syntax

C++/CLI

Python

public class RasterImagePagesChangedEventArgs : EventArgs

public ref class RasterImagePagesChangedEventArgs : public System.EventArgs

class RasterImagePagesChangedEventArgs(EventArgs):

Remarks

When images are added/inserted or removed from a RasterImage object, the RasterImage.PagesChanged event will fire with an instance of the RasterImagePagesChangedEventArgs class. This instance contains information on what pages has been changed. The following table will list the methods that would invoke the RasterImage.PagesChanged event and what values are expected.

Method	Values Expected
RasterImage.AddPage	For the source image (the image parameter): Action is RasterImagePagesChangedAction.Removed, StartIndex is the current page (RasterImage.Page) and Count is 1. For the destination image (The this or Me in Visual basic image): Action is RasterImagePagesChangedAction.Added, StartIndex is RasterImage.PageCount since the pages are added at the end and Count is 1.
RasterImage.AddPages	For the source image (the image parameter): Action is RasterImagePagesChangedAction.Removed, StartIndex is the value of the startIndex parameter and Count is the value of the count parameter. For the destination image (The this or Me in Visual basic image): Action is RasterImagePagesChangedAction.Added, StartIndex is RasterImage.PageCount since the pages are added at the end and Count is the value of the count parameter.
RasterImage.RemovePageAt	Action is RasterImagePagesChangedAction.Removed, StartIndex is the value of the pageIndex and Count is 1.
RasterImage.RemovePages	Action is RasterImagePagesChangedAction.Removed, StartIndex is the value of the startIndex parameter and Count is the value of the count parameter.
RasterImage.RemoveAllPages	Action is RasterImagePagesChangedAction.Removed, StartIndex is 1 and Count is RasterImage.PageCount.
RasterImage.InsertPage and RasterImage.ReplacePages	For the source image (the image parameter): Action is RasterImagePagesChangedAction.Removed, StartIndex is the current page (RasterImage.Page) and Count is 1. For the destination image (The this or Me in Visual basic image): Action is RasterImagePagesChangedAction.Added, StartIndex is the value of the index parameter and Count is 1.
RasterImage.InsertPages and RasterImage.ReplacePages	For the source image (the image parameter): Action is RasterImagePagesChangedAction.Removed, StartIndex is the value of the startIndex parameter and Count is the value of the count parameter. For the destination image (The this or Me in Visual basic image): Action is RasterImagePagesChangedAction.Added, StartIndex is the value of the index parameter and Count is the value of the count parameter.
RasterImage.Dispose	Action is RasterImagePagesChangedAction.Removed, StartIndex is 1 and Count is the number of pages in the current RasterImage.

Example

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing; 
using Leadtools.ImageProcessing.Core; 
using Leadtools.ImageProcessing.Color; 
using Leadtools.Dicom; 
using Leadtools.Drawing; 
using Leadtools.Controls; 
using Leadtools.Svg; 
 
 
public void PagesChangedExample() 
{ 
	RasterCodecs codecs = new RasterCodecs(); 
	codecs.Options.Load.AllPages = true; 
 
	string srcFileName1 = Path.Combine(LEAD_VARS.ImagesDir, "eye.gif"); 
	string srcFileName2 = Path.Combine(LEAD_VARS.ImagesDir, "image1.cmp"); 
 
	// Load the multi-page image 
	RasterImage srcImage = codecs.Load(srcFileName1); 
	srcImage.PagesChanged += new EventHandler<RasterImagePagesChangedEventArgs>(Image_PagesChanged); 
 
	// Show the number of pages in this file 
	Console.WriteLine("Pages in the image: {0}", srcImage.PageCount); 
 
	// Show and change the active page 
	Console.WriteLine("Active page: {0}", srcImage.Page); 
	srcImage.Page = 3; 
	Console.WriteLine("Active page: {0}", srcImage.Page); 
	srcImage.Page = 1; 
 
	// Load a single page image and add it to the end 
	RasterImage pageImage = codecs.Load(srcFileName2); 
	pageImage.PagesChanged += new EventHandler<RasterImagePagesChangedEventArgs>(Image_PagesChanged); 
	Console.WriteLine("Adding a single page"); 
	srcImage.AddPage(pageImage); 
	Console.WriteLine("Pages in the image: {0}", srcImage.PageCount); 
 
	// Load a multi page image and add a few pages to this image 
	pageImage = codecs.Load(srcFileName1); 
	pageImage.PagesChanged += new EventHandler<RasterImagePagesChangedEventArgs>(Image_PagesChanged); 
	Console.WriteLine("Adding multi-pages"); 
	srcImage.AddPages(pageImage, 1, 2); 
	Console.WriteLine("Pages in the image: {0}", srcImage.PageCount); 
 
	// Insert a page in the middle 
	Console.WriteLine("Inserting a page"); 
	srcImage.InsertPage(4, pageImage); 
	Console.WriteLine("Pages in the image: {0}", srcImage.PageCount); 
 
	// Insert the rest of the pages at the beginning 
	Console.WriteLine("Inserting pages"); 
	srcImage.InsertPages(0, pageImage, 1, -1); 
	Console.WriteLine("Pages in the image: {0}", srcImage.PageCount); 
 
	// Remove the first page 
	Console.WriteLine("Removing a page"); 
	srcImage.RemovePageAt(1); 
	Console.WriteLine("Pages in the image: {0}", srcImage.PageCount); 
 
	// Remove the last 3 pages 
	Console.WriteLine("Removing pages"); 
	srcImage.RemovePages(srcImage.PageCount - 3, -1); 
	Console.WriteLine("Pages in the image: {0}", srcImage.PageCount); 
 
	// Remove all the pages (leaves 1) 
	Console.WriteLine("Removing all pages"); 
	srcImage.RemoveAllPages(); 
	Console.WriteLine("Pages in the image: {0}", srcImage.PageCount); 
 
	srcImage.Dispose(); 
	codecs.Dispose(); 
} 
 
void Image_PagesChanged(object sender, RasterImagePagesChangedEventArgs e) 
{ 
	Console.WriteLine("Added = {0}, Index = {1}, Count = {2}", e.Action, e.StartIndex, e.Count); 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images"; 
}

Requirements

Target Platforms

Reference

RasterImagePagesChangedEventArgs Members

Leadtools Namespace

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Help Version 22.0.2023.5.16