Run javascript function only for one time (first page load)

Question

I'd like to run this javascript function only for one time (first page load). Is it possible? Thank you

<div id="pag">
<script type="text/javascript">

var framekiller = true;

window.onbeforeunload = function () {
if (framekiller) {
    return "Click on stay on this page";
}
};

</script>

<iframe scr="http://www.example.com/page-with-javascript-framebuster.html"></iframe>
</div>

Answer 1

You should use global variables in javascript.

<script type="text/javascript">

window.framekiller = true;

window.onbeforeunload = function () {
if (window.framekiller) {
    return "Click on stay on this page";
}
};

</script>

<iframe scr="http://www.example.com/page-with-javascript-framebuster.html"></iframe>

And put somewhere else, another javascript snipper, who turn this variable into false, and do other things.. eg opens a new link? To turn it back to false, use:

window.framekiller = false;