js获取url参数的function

<script language="javascript" type="text/javascript"> 
//js获取url参数的function
function request(paras){ 
var url = location.href;   
var paraString = url.substring(url.indexOf("?")+1,url.length).split("&");   
var paraObj = {}   
for (i=0; j=paraString[i]; i++){   
paraObj[j.substring(0,j.indexOf("=")).toLowerCase()] = j.substring(j.indexOf 
("=")+1,j.length);   
}   
var returnValue = paraObj[paras.toLowerCase()];   
if(typeof(returnValue)=="undefined"){   
return "";   
}else{   
return returnValue;   
}   
} 

</script>