js执行服务器端事件

 <script language="javascript" type="text/javascript">
        function check()
        {
            $.ajax({
                        type: "POST",
                        url: "xxx.aspx",
                        data: "aa="+aa,
                        success: function(msg){
                            if(msg=="OK")
                            {
                                action();
                            }
                            else
                            {
                                if(confirm("请确认是否继续？"))
                                {
                                    action();
                                }
                            }
                        }
                    });
        }
        function action()
        {
            document.getElementById("<%= btn.ClientID %>").click();
        }