Random Unique

Hi
I am looking for help in develping my new project which involves selecting numbers, both randomly and uniqely. I have on stage 128 dynamic text boxes named myTextField1, myTextField2 etc etc up to 128, and I want to fill each box with a unique number from 1-128
I would like to use a button to run this code and if possible to fill each box individually that is box1 then box2 etc.
This is the code I am trying run but I cannot get it to give me 128 different numbers, it fills the fields ok but there are duplicates.

for (i=1; i<129; i++) {
   var temp:TextField = _root["myTextField" + i];
   temp.text = randFun();
}
function randFun() {
	var randomPick:Number = Math.ceil(Math.random()*128);
	return randomPick;
}

Any help please
Bern