动态加载js文件 document.createElement

var Rash=true; 
var msg=""; 

function norash() 
{ 
if (confirm("确定要取消吗")) 
Rash=false; 
} 

 function rashit() 
{ 
setInterval('getrss()',Inttime); 
} 

function getrss() 
{ 
        if (Rash==true) 
        { 
        head=document.getElementsByTagName('head').item(0); 
        script=document.createElement('script'); 
        script.src='INCLUDE/AutoUpdate.asp'; 
        script.type='text/javascript'; 
        script.defer=true; 
        void(head.appendChild(script)); 
        window.status=msg; 
        } 
} 
rashit();