asp.net IFrame scroll bar push to top . .

<script type="text/javascript">
  function gotop() {
    scroll(0,0);
  }
</script>

<iframe id="myframe"
    onload="try { gotop() } catch (e) {}"
    src="http://yourframesource"
    width="100%" height="999"
    scrolling="auto" marginwidth="0" marginheight="0"
    frameborder="0" vspace="0" hspace="0" >
</iframe>