基本代码就以下三行，
谁给解释解释，
<script language="JavaScript">
blur();
</script>
以下是全也代码：
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD><TITLE>背投广告</TITLE>
<META http-equiv=Content-Type content="text/html; charset=gb2312">
<META content="MSHTML 6.00.2800.1458" name=GENERATOR>
<script type="text/javascript" src="http://image2.sina.com.cn/home/sinaflash.js"></script>
</HEAD>
<BODY bgColor=#ffffff leftMargin=0 topMargin=0 marginheight="0">
<SCRIPT lanaguage="javascript">
var par = location.search.substr(1);
var ary = par.split("${}");
if(ary[1]!="swf")
document.write("<a href='" + ary[0] + "' target = '_blank'><img src='" + ary[2] + "' WIDTH=750 HEIGHT=450 border = 0></a>");
else {
document.write("<div id='backPop'>不支持Flash</div>");
var FlashbackPop = new sinaFlash(ary[2], "ad_backPop", "750", "450", "7",
"", false, "High");
FlashbackPop.addParam("wmode", "opaque");
FlashbackPop.write("backPop");
}
</SCRIPT>
<script language="JavaScript">
blur();
self.moveTo(100,50);
self.resizeTo(760,450);
self.resizeTo(760,450+(450-self.document.body.clientHeight));
blur();
</script>
</BODY></HTML>