function goback_js(str,url){
	if(document.getElementById("divbill")){document.getElementById("divbill").style.visibility="hidden";}
	alert(str);
	if(url==""){
 	   window.history.go(-1);
	}else if(url=="close"){
       window.close();
	}else{
	   window.location.href=url;
	}
}