document.onreadystatechange=function(){ 
if(document.readyState=="complete"){ 
        document.getElementById('loading_div').style.display='none'; 
    } 
} 
var str="<div id='loading_div' style='position:absolute;width:108%;height:108%; "
+"left:0px;top:0px;background-color:#ffffff;filter:alpha(opacity=100)'> "
//+"<div style='text-align:center;padding-top:200px'> "
//+"正在加载数据，请稍候." 
//+"<hr style='height:1px;width:50%'> "
//+"Loading "
//+"</div>"

+"<div id='Layer1' style='width:100%; height:100%; overflow:hidden; "
+"padding-top:expression((this.offsetHeight-myImage.offsetHeight)/2);' align='center'>"
+"<img src='os/images/ajax-loader.gif' align='absmiddle' id='myImage'>"
+"</div>"

+"</div> "
document.write(str);