Simple AS3 question

I am trying to make a button click change a variable …just learning about as3 and this will help me solve a bigger problem.

why does it not work

var varOne = “test”;

stop();

btnOne.addEventListener(MouseEvent.CLICK, click);

function click(evt:MouseEvent):void {
varOne = “sheep go bhaa”;
}

theCode.text = varOne;

in this is very rough code as i have no clue what I am doing