<script type="text/javascript" src="jquery.js"></script>
  <script type="text/javascript">
    function verify(){
     var jqueryobj=$("#result");
     jqueryobj.innerHTML="正在登陆中";
     var forms={username:$("#username"),password:$("#password")};
     var myAjax=new Ajax.Request(login.do,{method:'post',parameters:$("#forms").toQueryString(),onComplete:callback});这一句运行不能通过
     
    }
     //回调函数
      function callback(data){
        //找到保存结果信息的节点
       var resultobj= $("#result");
       resultobj.html(data);
    }
  </script>
  <body>
   <form action="" method="get">
       用户ID:<input type="text" id="username" name="username"><span id="result"></span><br>
       密码:<input type="password" id="password" name="password"><br>
       <input type="button" value="登录" onclick="verify()">
   </form>
  </body>
</html>
Action部分:
public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {
        UserForm userForm =(UserForm)form;
        if(userForm.getUsername().equals("yangtao")){
         response.getWriter().write(userForm.getUsername()+"登录成功!��¼�");
        }else{
         response.getWriter().write(userForm.getUsername()+"��¼ʧ�ܣ�登录失败!");
        }

return null;
}