Help PLZ... Action Script

1

hey guys im new to this forum. also new to flex 3.
i have basic knowledge about flex… still a beginner (just started learning from past few days)

i am getting this error very often.This might be a silly mistake, but still im not able to recognize whats the mistake… PLZ any one help me…


<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute">
<mx:Script>
    <![CDATA[
        var loader:URLLoader = new URLLoader();
        //loader.load(new URLRequest("external.txt"));
        //loader.addEventListener(Event.COMPLETE, onComplete);
        function onComplete(event:Event):void
        {
            external_txt.text&#65279; = event.target.data;
        }
    ]]>
</mx:Script>
<mx:TextArea x="148" y="34" height="110" id="external_txt"/>
</mx:Application>

The commented lines are place where i am getting errors:

on line //loader.load(new URLRequest(“external.txt”)); i get error as follows

1120: Access of undefined property loader.

online //loader.addEventListener(Event.COMPLETE, onComplete); i get following two errors,

1120: Access of undefined property loader.
1120: Access of undefined property onComplete.

so whats the problem here…?
URGENT PLZ…!!