JS的Ajax与后端交互数据的实例

$.ajax({    type: "post",    url: "http://localhost:8080/ccnb/user/login",    data: {     "telephone": login_name,     "password": login_password    },    dataType: "json",//   contentType:'application/json',    success: function (data) {     alert(data.Flag);     alert(data.Msg);      }     },    error: function (XMLHttpRequest, textStatus, errorThrown) {     alert(XMLHttpRequest.status);     alert(XMLHttpRequest.readyState);     alert(textStatus);    },   });