倒计时到期时自动提交

Question

如何在时间到期时自动提交

    <script language="javascript" type="text/javascript">
    $(document).ready(function() {

       $("#online").load("./tmr.php");
       var refreshId = setInterval(function() {
       //alert("aa");
          $("#online").load('./tmr.php');
          $.ajax({
                           type: "POST",
                           url: "./update.php",
                           data: "stdID="+aa
         })
       }, 1000);
       $.ajaxSetup({ cache: false });
    });

    </script>

the php code is

<?php
session_start();
$aa = $_SESSION['member'];

include 'connect.php';
$result = mysql_query("SELECT tmr_left FROM account WHERE member='$aa'");
$count = mysql_num_rows($result);
$tmr = mysql_result($result,0,"tmr_left");


$dateFormat = "d F Y -- g:i a";

$targetDate = time() + (30*60);//Change the 25 to however many minutes you want to countdown

$actualDate = time();

$secondsDiff = $tmr; = 1800 = 30 mins

$remainingDay    = floor($secondsDiff/60/60/24);

$remainingHour  = floor(($secondsDiff-($remainingDay*60*60*24))/60/60);

$remainingMinutes = floor(($secondsDiff-($remainingDay*60*60*24)-($remainingHour*60*60))/60);

$remainingSeconds = floor(($secondsDiff-($remainingDay*60*60*24)-($remainingHour*60*60))-($remainingMinutes*60));

$actualDateDisplay = date($dateFormat,$actualDate);

$targetDateDisplay = date($dateFormat,$targetDate);


echo $remainingMinutes.":".$remainingSeconds;

?>

并按间隔保存

    <?php
    include 'connect.php';
    $result = mysql_query("SELECT tmr_left FROM account WHERE member='".$_POST['stdID']."'");
    $tmr = mysql_result($result,0,"tmr_left");
    $tmr -=1;
    $command = mysql_query("UPDATE account SET tmr_left='".$tmr."' WHERE member='".$_POST['stdID']."'") or die(mysql_error());
    ?>

它不是纯粹的JavaScript，但是当时间用完时，是否有任何可行的方法来放置.submit（）？每秒在我的数据库中保存的时间