初次接触DWR,查看资料时,遇到个简单语法问题

Question

处理业务代码:public class UserLogic {   
    public User alterUser(User user){   
        user.setUserName("lukuijun");   
        user.setPassword("lukuijun");   
        return user;   
    }   
}  调用业务代码的JS:
<script type="text/javascript">  
        function show(){   
            var userName=$("userName").value;   
            var password=$("password").value;   
            var obj={userName:userName,password:password};   
            UserLogic.alterUser(obj,function(data){   
                $("userName").value=data.userName;   
                $("password").value=data.password;   
            });   
           
        }   
    </script>  疑惑的是:var userName=$("userName").value; 
var obj={userName:userName,password:password};这两句代码怎么解释呢?

Answer 1

var userName=$("userName").value
  就相当于Document.getElementById("userName").value();
var obj={userName:userName,password:password}; 
  这是一个JSON格式的 前面 是KEY后面的是值。