function addCssByLink(url){ 
    var doc=document;  
    var link=doc.createElement("link");  
    link.setAttribute("rel", "stylesheet");  
    link.setAttribute("type", "text/css");  
    link.setAttribute("href", url);      
    var heads = doc.getElementsByTagName("head");  
    if(heads.length)  
        heads[0].appendChild(link);  
    else 
        doc.documentElement.appendChild(link);  
}
function addCssByStyle(cssString){  
    var doc=document;
    var style=doc.createElement("style");  
    style.setAttribute("type", "text/css");  
    if(style.styleSheet){// IE  
        style.styleSheet.cssText = cssString;
    } else {// w3c  
        var cssText = doc.createTextNode(cssString);  
        style.appendChild(cssText);  
    }  
    var heads = doc.getElementsByTagName("head");  
    if(heads.length)  
        heads[0].appendChild(style);  
    else 
        doc.documentElement.appendChild(style);  
}  

    //动态添加js
    var mapJs = doc.createElement("script");
    mapJs.setAttribute("type","text/javascript");
    mapJs.setAttribute("src","http://maps.google.com/maps/api/js?sensor=false");
    //var heads = doc.getElementsByTagName("head");
    doc.documentElement.appendChild(mapJs);