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StartRedirecting Method

Starts file I/O redirection.
public void StartRedirecting() 
Public Sub StartRedirecting()  
public void startRedirecting() 
void StartRedirecting();  

LEADTOOLS I/O redirection allows you to replace the default input/output methods for opening, reading, writing, seeking, and closing files.

For example, you can redirect all the library I/O methods to your own I/O methods to load/save images from your own streams.

Once you call StartRedirecting, all subsequent file I/O operation will fire the following events:

Event Operation
RedirectOpen When the toolkit is trying to open a file
RedirectRead When the toolkit is trying to reading from a file
RedirectWrite When the toolkit is trying to writing to a file
RedirectSeek When the toolkit is trying to seeking into a file
RedirectClose When the toolkit is trying to closing a file

Call StopRedirecting to reset the I/O methods back to the defaults.


This example demonstrates overriding the default IO routines.

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing; 
using Leadtools.ImageProcessing.Color; 
using Leadtools.Svg; 
// Redirect Read event example 
FileStream myStream; 
// Redirect Open event example 
private void Codecs_Open(object sender, CodecsRedirectOpenEventArgs e) 
	myStream = new FileStream(e.FileName, e.Mode); 
	e.Success = true; 
// Redirect Seek event example 
private void Codecs_Seek(object sender, CodecsRedirectSeekEventArgs e) 
	myStream.Seek(e.Offset, e.Origin); 
	e.Offset = myStream.Position; 
// Redirect Read event example 
private void Codecs_Read(object sender, CodecsRedirectReadEventArgs e) 
	byte[] byteBuffer = new byte[e.Count]; 
	myStream.Read(byteBuffer, 0, e.Count); 
	Marshal.Copy(byteBuffer, 0, e.Buffer, e.Count); 
	e.Read = e.Count; 
	Console.WriteLine("The number of bytes that read request should copy to the buffer is : {0}", e.Count); 
	Console.WriteLine("The actual number of bytes that this read request has copied to Buffer is : {0}", e.Read); 
// Redirect Write event example 
private void Codecs_Write(object sender, CodecsRedirectWriteEventArgs e) 
	byte[] byteBuffer = new byte[e.Count]; 
	Marshal.Copy(e.Buffer, byteBuffer, 0, e.Count); 
	myStream.Write(byteBuffer, 0, e.Count); 
	e.Written = e.Count; 
	Console.WriteLine("The number of bytes that write request should copy from the buffer is : {0}", e.Count); 
	Console.WriteLine("The actual number of bytes that this write request has copied from Buffer is : {0}", e.Written); 
// Redirect Close event example 
private void Codecs_Close(object sender, CodecsRedirectCloseEventArgs e) 
		public void StartRedirectingExample() 
	RasterCodecs codecs = new RasterCodecs(); 
	codecs.RedirectOpen += new EventHandler<CodecsRedirectOpenEventArgs>(Codecs_Open); 
	codecs.RedirectSeek += new EventHandler<CodecsRedirectSeekEventArgs>(Codecs_Seek); 
	codecs.RedirectRead += new EventHandler<CodecsRedirectReadEventArgs>(Codecs_Read); 
	codecs.RedirectWrite += new EventHandler<CodecsRedirectWriteEventArgs>(Codecs_Write); 
	codecs.RedirectClose += new EventHandler<CodecsRedirectCloseEventArgs>(Codecs_Close); 
	string srcFilename = Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp"); 
	RasterImage image = codecs.Load(srcFilename); 
	codecs.Save(image, Path.Combine(LEAD_VARS.ImagesDir, "Image1_redirect.jpg"), RasterImageFormat.Jpeg, image.BitsPerPixel); 
	// Clean up 
static class LEAD_VARS 
   public const string ImagesDir = @"C:\LEADTOOLS21\Resources\Images"; 

Target Platforms

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