很好用的JS遮盖层,Jquery,javascript遮盖层
    <input type="button" name="ss" value="cc" onclick="openNewDiv()" />
<SCRIPT language="javascript" type="text/javascript">
	var docEle = function()
	{
	    return document.getElementById(arguments[0]) || false;
	}
	function openNewDiv()
	{
	    var m = "mask";
	    if (docEle(m)) document.body.removeChild(docEle(m));	   
	    //mask遮罩层	
	    var newMask = document.createElement("div");
	    newMask.id = m;
	    newMask.style.position = "absolute";
	    newMask.style.zIndex = "1";
	    _scrollWidth = Math.max(document.body.scrollWidth,document.documentElement.scrollWidth);
	    _scrollHeight = Math.max(document.body.scrollHeight,document.documentElement.scrollHeight);
	    newMask.style.width = (_scrollWidth-20) + "px";
	    newMask.style.height = (_scrollHeight-20) + "px";
	    newMask.style.top = "0px";
	    newMask.style.left = "0px";
	    newMask.style.background = "#e8e8e8";
	    newMask.style.filter = "alpha(opacity=40)";
	    newMask.style.opacity = "0.40";
	    newMask.innerHTML ="<div  align='center' style='margin-top: 80px;'><img src='..//loading.gif' width='16' height='16'  style='CURSOR: pointer'><br/><br/><font color='#ff0000'><b>请等待.......</b></font><div>";
	    document.body.appendChild(newMask);
	}
</SCRIPT>