iframe高度自动调整

<iframe src="default.ASP"  style="width: 100% ; border: 0px" frameborder=0 scrolling=yes name=right onload="init()" border="0"></iframe>
<script>
var lastHeight;
function init() {
    autojudge();
    lastHeight= right.document.body.scrollHeight;
    setInterval(function(){
        if(right.document.body.scrollHeight!=lastHeight) {
            autojudge();
            lastHeight= right.document.body.scrollHeight;
            }
        },1);
}
function autojudge(){
    document.all('right').height=right.document.body.scrollHeight + 20;
    }
</script>