Calling a function from aspx.cs

Hi i have a fucntion which i need to call here on page load of the aspx.cs
the function on the html file is this
<script type="text/javascript" src="JwPlayer/jw/jwplayer.js"></script>
<div id="mediaplayer"></div>
<script type="text/javascript">
function PlayMovie(url)
{
jwplayer("mediaplayer").setup({
flashplayer: "JwPlayer/jw/player.swf",
file: "Movies/"+url,
height:"500",
width: "700",
image: "Movies/movieImage.jpg",
events: { onComplete: function() { alert("the video is finished!"); } }
});
}
</script>
now how can i call the function with the paramter that im going to get in the code,if you found some errors please tell me
btw its a jw player for playing movies
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