How to use correct external path for so.addVariable

hi everyone,

i was trying to load an dynamic swf by an external path using the addVariable of swfObject. But i seem to be lost when im already trying to call the path of the swf. on the loadMovie function, i noticed that “_level0.bg” which is a String and myRandom as Number is not possible to concatenate. Can I ask anyone how to be able to call this path properly so that i can load the swf?

Anyone’s suggestion is greatly appreciated. I attached the code here so anyone can see what i’ve done wrong in the code.

 
_root.onLoad = function() {
 var myRandom = Math.floor(Math.random() * _level0.totalPic) + 1;
 _root.bg_mc.loadMovie("_level0.bg" + myRandom); // it should be like _level0.bg1;
}


<script type="text/javascript">
   var so = new SWFObject("core.swf", "mymovie", "764", "500", "8", "#FFFFFF");
   so.addParam("wmode", "window");
   so.addParam("salign", "t");
   so.addParam("scale", "noscale");
  so.addVariable("totalPic", "21");
  so.addVariable("bg1", "bg/1.swf");
  so.addVariable("bg2", "bg/2.swf");
  so.addVariable("bg3", "bg/3.swf");
  so.write("flashcontent");
</script>

cheers,
_scriptRookie