page effect can be displayed normally, but open the console and see that there is an error.
 this is an error 
  
this is the code
function getRooms(pagenum){
    var xmlhttp=null
    if(window.XMLHttpRequest){
        xmlhttp= new XMLHttpRequest()
    }else {
        xmlhttp=new ActiveXObject("Microsof.XMLHTTP")
    }
    
    xmlhttp.onreadystatechange=function(){
        
        var data=JSON.parse(xmlhttp.responseText); 
        
        if(xmlhttp.readyState==4&&xmlhttp.status==200){
            
            var tbody=document.getElementsByTagName("tbody")[0];
            tbody.innerHTML="";
            var list=data.Data;
            var count=data.countpage;
                 
            for(var i=0;i<list.length;iPP){
                
                var num = i + (count - 1) * 10 + 1;
                
                var content="<tr id="+list[i].id+">"+
                "<td>"+num+"</td>"+
                "<td class="mrName">"+list[i].name+"</td>"+
                "<td>"+list[i].state+"</td>"+ 
                "<td>"+list[i].meetcount+"</td>"+ 
                "<td>"+list[i].username+"</td>"+
                "<td>"+list[i].begintime+"</td>"+
                "<td>"+
                    "<button class="deleteInfo"></button>"+
                    "<button class="changeInfo"></button>"+
                "</td>"+
                "</tr>"        
                
                tbody.innerHTML+=content
                        
                
            }
        }
    }
    
    xmlhttp.open("post","/Meet/ListAllMeet.do",true)
    
    xmlhttp.setRequestHeader("content-type", "application/x-www-form-urlencoded")
    
    xmlhttp.send("pagenum="+pagenum)
}