Detect URLRequest variable change?

Alright, so I'm using AS3 to get variables from a plain text file. The variables are loaded, and assigned as a variable in Flash.

Code:

---

var checkNew:Timer = new Timer(2000);
checkNew.addEventListener(TimerEvent.TIMER, reConnect);
checkNew.start();
function reConnect(evt:TimerEvent):void{
        var request:URLRequest = new URLRequest("vars/vars.php?"+new Date().getTime());
        request.method = URLRequestMethod.GET;
        var loader:URLLoader = new URLLoader();
        loader.dataFormat = URLLoaderDataFormat.VARIABLES;
        loader.addEventListener(Event.COMPLETE, completeHandler);
        loader.load(request);
}
function completeHandler(evt:Event) {
        var gamertagText = evt.target.data.gamertag;
        addEventListener(Event.ENTER_FRAME, gamertagShow);
        function gamertagShow(event:Event){
                gamertagHolder.gamertag.text = String(gamertagText);
        }
}

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So basically as you can see here, the gamertag is loaded from a plain text PHP file and converted into a variable. What I need to be able to do is tell whether or not that variable has changed (ex. 1 changed to 2). Is there a way of doing this in AS3?

You create a variable somewhere at the beginning of your script:
var varChanged:String = "";
Then after this line you write:
var gamertagText = evt.target.data.gamertag;
if(varChanged != null && varChanged != gamertagText)
{
trace("no");
}
else if(varChanged == gamertagText)
{
trace("yes");
}
varChanged = gamertagText;