Actionscript 3: How to make movieclip variables work with variables on stage (Healthbar Help) - variables

Question

I am totally new at this whole programming thing, and I really need help. So basically, I'm trying to make a healthbar that will increase or decrease depending on what button is clicked. I made a healthbar movieclip with 101 frames (I included zero) and put this in the actionscript layer of the movieclip:
var health:Number = 0;
if(health == 0)
{
gotoAndStop("1")
}
if(health == 1)
{
gotoAndStop("2")
}
if(health == 2)
{
gotoAndStop("3")
}
and on and on like so. Basically, on the stage itself, I have a button called fortyfiveup_btn that is commanded to do this:
var health:Number = 0;
fortyfiveup_btn.addEventListener(MouseEvent.CLICK, fortyfiveupClick);
function fortyfiveupClick(event:MouseEvent):void{
health = health+45
}
I quickly realized that both health variables, the one for the button and the one for the healthbar will not interact. How can I make it so if the button is clicked, the health goes to the relevant frame or percentage?
Thanks for any answers, and I appreciate all the help I can get :)

Answer 1

If the answer == yes to my comment you should do this:
You need to give the movieclip an instancename (perhaps lifebar) and from stage you can access the health inside the "lifebar" with lifebar.health.
So you need this inside your stage:
//You can delete the var health:Number = 0;
fortyfiveup_btn.addEventListener(MouseEvent.CLICK, fortyfiveupClick);
function fortyfiveupClick(event:MouseEvent):void{
//You can write this, too: lifebar.health += 45;
lifebar.health = lifebar.health+45;
}
You can even optimize your lifebar script, don't use 101 times the if(health == x) you can use this, too:
gotoAndStop(health + 1);
(I think this is inside an ENTER_FRAME event?)
EDIT:
Some error countermeasures:
//Don't let health decrease below 0
if(health < 0) health = 0;
//And don't above 100
else if(health > 100) health = 100;
gotoAndStop(health + 1);
Use int instead of Number when you don't use decimal numbers and uint when you don't use negative integers (this bugs when the number can drop under 0, so for your health we take int):
health:int = 0;