Error trapping not happening

programming flash
1

I want to load as many bitmaps as are in a folder, looping back to the 1st when I run out of files. I’ve modified code I found elsewhere for the error trapping, but it doesn’t work.

Instead of getting the traced 'Errorhandler: ’ + event, I get ‘Error #2044: Unhandled IOErrorEvent:. text=Error #2035: URL Not Found.’ in the output window.

Any ideas what I’m missing?

import flash.net.URLLoader;
import flash.display.Loader;
import flash.events.*;
import flash.events.IOErrorEvent;

var inc:Number=1;

function errorHandler(event:ErrorEvent):void {
	trace("errorHandler: " + event);
}

var timer:Timer=new Timer(1000);
timer.addEventListener(TimerEvent.TIMER, onTimer);
timer.start();


function onTimer(evt:TimerEvent):void {
	var ldr = new Loader();
	ldr.addEventListener(IOErrorEvent.IO_ERROR, errorHandler);
	ldr.addEventListener(SecurityErrorEvent.SECURITY_ERROR, errorHandler);
	ldr.load(new URLRequest("tag_"+inc+".jpg"));
	inc++;
	addChild(ldr);
}