jquery - Backbone.Syphon - always return empty object -

i using backbone.syphon plugin in backbone.marionette app. when click on submit button form, getting empty object({}).. don't know reason that,

any 1 me find issue pelase?

here view.js

define([     'jquery','underscore',     'backbone','marionette',     'text!./templates/loginview.html'],     function($,_,backbone,marionette,template){         "use strict";          var loginview = backbone.marionette.itemview.extend({              classname:'col-xs-12 col-md-4 col-md-offset-4',              template:_.template(template),              events:{                 "submit form" : "loginsubmit"             },              loginsubmit:function(e){                 e.preventdefault();                 var data = backbone.syphon.serialize(e.target);                 console.log(data); //always return empty object.             }          });          return loginview;     } ); 

here form:

<form action="#" id="loginform" class="form-horizontal" role="form">     <legend>         <fieldset>             <label for="username">username</label>             <input type="text" value="" id="username" class="form-control" placeholder="enter username">             <label for="password">password</label>             <input type="text" id="password" value="" class="form-control" placeholder="enter password">             <input type="submit" class="btn btn-primary" value="login" id="login">         </fieldset>     </legend> </form> 

i updated form html adding name elements. works fine.

here updated html:

<form action="#" id="loginform" class="form-horizontal" role="form">     <legend>         <fieldset>             <label for="username">username</label>             <input type="text" value="" id="username" name="username" class="form-control" placeholder="enter username">             <label for="password">password</label>             <input type="text" id="password" value="" name="password" class="form-control" placeholder="enter password">             <input type="submit" class="btn btn-primary" value="login" id="login">         </fieldset>     </legend> </form>