遮罩 半透明
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<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>无标题文档</title>
<script type="text/javascript" src="http://blog.colorbird.com/mootools_demo/script/mootools.js"></script>
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function show(){
/*定义两个DIV showbg是遮盖层 showdiv是弹出窗口*/
var showbg = new Element("DIV");
var showdiv = new Element("DIV");
showbg.id = "showbg";
/*定位*/
showbg.injectAfter($('main'));
showdiv.injectInside($(showbg));
/*设定遮盖层属性 filter是IE识别的透明 moz是FF的透明*/
/*设定层属性 filter是IE识别的透明 moz是FF的透明*/
$('showbg').setStyles('background-color:#000;filter:alpha(opacity=40);-moz-opacity:0.4;position:absolute;top:0;left:0;z-index:1000');
/****************这部分为修改**************************/
var textindiv = "<a href=javascript:void(0) onclick=removeshow()>关闭</a>";
showdiv.setHTML(textindiv);
/******************************************************/
dosize();
window.addEvents({
'resize': function(){dosize();},
'scroll': function(){dosize();}
});
function dosize(){
showdiv.setStyle('width','100px');
showdiv.setStyle('background','#fff');
showbg.style.width = window.getWidth() + "px";
showbg.style.height = window.getScrollHeight() + "px";
showbgsx = window.getWidth();
showbgsy = window.getHeight();
showdivx = $(showdiv).getCoordinates().width;
showdivy = $(showdiv).getCoordinates().height;
showdivt = window.getScrollTop();
showdivtop = Math.floor((showbgsy - showdivy) / 2)+showdivt;
showdivleft = Math.floor((showbgsx - showdivx) / 2)-18;
showdiv.setStyles('background-color:#fff;position:absolute;top:'+showdivtop+'px;left:'+showdivleft+'px;z-index:1001');
}
function removeshow(){
$('showbg').remove();
}
}
</script>
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<a href="javascript:void(0);" onclick="show()">登陆</a>
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<a href="javascript:void(0);" onclick="show()">登陆</a>
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