Transform text read from file into number

Hello,

I am using Flash 8 Proffessional, and I am trying to read some text from a text file, increment this text with 1 and rewrite it back on the file. My text file looks like this:

Name: ffile.txt
Content: &counter=0&

What i want is to increment the counter everytime i press a button, and write it back to file.

I am readimg from file like this:

on (release)
{

var lv:LoadVars = new LoadVars();
lv.onData = function(thetext:String)
{
unu.text = (thetext);
}
lv.load(“ffile.txt”);
}

unu.text is a dynamic text field which shows me the value of counter.

I test the movie, i press the button, and yes the dynamic text field shows up the value read from text file: 0, 2, 8, or whatever I set it earlier. But I want to use this value to add 1.
I have tried:
trace(Number(unu.text)+1) - nothing,
tried trace(Number(counter)+1) - nothing,
trace(parseInt(unu.text)+1) - nothing,
trace(parseInt(Number(counter))+1 - nothing.
I just can’t find a way to convert this text from file into number.
Do you guys know a way to do this? An example perhaps. Anything.
I am trying to make a visitor counter, and my host does not permit PHP scripts or any of this kind, so I have to read text files and increment the visits myself.

Thank you.