窗口加载蒙板，内嵌网页

//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;
}