//看不清，换图
function chgImage(obj){
   var r = Math.random(); 
   if(obj.src.indexOf("2.jsp")!=-1)
       obj.src = "/inc/img.jsp";
   else
       obj.src = "/inc/img2.jsp";
} 
//登录检测
 function toLogin(needcheck){
 	    if(needcheck){
 	        if(!checkForm(document.loginForm))return;
 	    }
 	    function loginCallback(data){
 	        var d = JSON.parse(data);
 	        if(d.err!=''){
 	           if(needcheck){
	 	           alert(d.err);
	 	           window.location.reload();
 	           }
 	           return;
 	        }else{
 	            $('loginView').innerHTML = d.html;
 	        }
 	    }
 	    Util.formRequest(document.loginForm,{success:loginCallback,type:'plain'});
 }