Js > as

Ok, I know some of youre are fermiliar with loading JS variables into Flash
The way I do it is like this:

 <script language="JavaScript">
function setPage(newPage) {
    if (window.document.content) {
        window.document.content.SetVariable("myHTMLvar", newPage);
    }
}
</script>

So Ive got a flash movie on the site named “content”. I get the variable “newPage” from a JS in an iframe which looks like this:

<script language="JavaScript">
    parent.setPage("lol"); 
</script>

Ok so far so clear.
I use an empty MC in my flash movie with an onClipEvent(enterFrame) handler to check wether a variable is assigned or not.
So this script keeps running every frame.

Now my question is if its possible to execute a function ONCE through JS. So i dont need the onClipEvent handler to check if a variable is assigned.

Does anyone how to solve this?