clientHeight와 box의 offsetHeight로 초기의 vertical-middle값을 구한뒤,
scrollTop으로 scroll되는 값을 계산게 된다.
<![CDATA[<script type="text/javascript">
function test() {
var tbox = document.getElementById("box");
var lpos = parseInt(document.body.offsetWidth/2) - parseInt(tbox.offsetWidth/2) + "px
var tpos = parseInt(document.documentElement.clientHeight/2) +
parseInt(document.documentElement.scrollTop ) - parseInt(tbox.offsetHeight/2) + "px";
tbox.style.left = lpos + "px";
tbox.style.top = tpos + "px
return false;
}
</script>
<body>
<div id="box"></div>
<div style="margin:0; padding:0; border:none; background:none; float:none; clear:none; z-index:0"></div>
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