javascript 窗口加载蒙板 内嵌网页内容

//初始化导航背景，iframe容器
function fnDaoHangBg()
{
var h = fnGetHeight(),w = fnGetWidth();//获取背景窗口大小
if(!$('divDaoHangBg'))
{
var div = $C('div');//创建背景蒙板
div.id = 'divDaoHangBg';
div.style.backgroundColor = 'black';
div.style.position = 'absolute';
div.style.filter = 'alpha(opacity=80)';
div.style.opacity = '.80';
div.style.zIndex = 100001;
div.style.left = 0;
div.style.top = 0;
div.style.width = w+'px';
div.style.height= h+'px';
document.body.appendChild(div);
}

if(!$('divDaoHangBgIframe'))
{
var iframe;
iframe = this.$C('IFRAME');//创建蒙板内的内嵌iframe容器，用于嵌入显示其他网页
iframe.id = 'divDaoHangBgIframe';
iframe.frameBorder = '0';
iframe.scrolling = "no";
iframe.style.overflow = 'hidden';
iframe.allowTransparency = 'true';
iframe.style.display = 'none';
iframe.style.width = w+'px';//800
iframe.style.height = h+'px';//620
iframe.style.marginTop = '75px';//800
$('divDaoHangBg').appendChild(iframe);
}
if(!$('divDaoHangBgClose'))
{
var div = $C('div');//创建关闭按钮在蒙板上
div.id = 'divDaoHangBgClose';
div.style.position = 'absolute';
div.style.backgroundImage='url(images/closb.gif)';
div.style.zIndex = 100003;
div.style.right = 10;
div.style.top = 20;
div.style.width = '82px';
div.style.height= '30px';
div.title='关闭';
div.style.cursor='hand';
div.onclick=function(){//点击时间 ，关闭蒙板
fnDaoHangBgClose();
};
$('divDaoHangBg').appendChild(div);
}
$('divDaoHangBgIframe').style.display='block';
$('divDaoHangBg').style.display='block';
}
//关闭蒙板
function fnDaoHangBgClose()
{
if(!$('divDaoHangBg')){return;}
if(!$('divDaoHangBgIframe')){return;}
$('divDaoHangBgIframe').src='';
$('divDaoHangBgIframe').style.display='none';
$('divDaoHangBg').style.display='none';
}
//调用，内嵌url
function fnDaoHangBgShow(url)
{
fnDaoHangBg();
$('divDaoHangBgIframe').src=url;
}