用于在线考试功能失败的Jquery倒数计时器

Question

我在网上考试中添加了一个计时器。如果时间结束，它应该停止测验并继续显示结果。问题是，每次我点击“下一个问题”按钮，时间重置，它也不会停止测验。

这是我到目前为止的代码。 计时器代码

<script>
        var c = 60;
        var t;
        timedCount();

        function timedCount() {

            var hours = parseInt( c / 3600 ) % 24;
            var minutes = parseInt( c / 60 ) % 60;
            var seconds = c % 60;

            var result = (hours < 10 ? "0" + hours : hours) + ":" + (minutes < 10 ? "0" + minutes : minutes) + ":" + (seconds  < 10 ? "0" + seconds : seconds);


            $('#timer').html(result);
            if(c == 0 ){
                setConfirmUnload(false);
                $("#myfm").submit();

            }
            c = c - 1;
            t = setTimeout(function(){ 
                timedCount() }
                , 1000);
        }
</script>

形式

echo "<form name=myfm method=post id=myfm action=quiz.php>";
echo "<table width=100%> <tr> <td width=30>&nbsp;<td> <table border=0>";
$n=$_SESSION[qn]+1;
echo "<tR><td><span class=style2>Que ".  $n .": $row[2]</style>";
echo "<tr><td class=style8><input type=radio name=ans value=1>$row[3]";
echo "<tr><td class=style8> <input type=radio name=ans value=2>$row[4]";
echo "<tr><td class=style8><input type=radio name=ans value=3>$row[5]";
echo "<tr><td class=style8><input type=radio name=ans value=4>$row[6]";
echo "<tr><td class=style8><input type=radio name=ans value=5>$row[7]";
if($_SESSION[qn]<mysql_num_rows($rs)-1)
echo "<tr><td><input type=submit name=submit value='Next Question'></form>";
else
echo "<tr><td><input type=submit name=submit value='Get Result'></form>";
echo "</table></table>";

获取结果代码

if($submit=='Get Result' && isset($ans))
        {
                mysql_data_seek($rs,$_SESSION[qn]);
                $row= mysql_fetch_row($rs); 
                mysql_query("insert into mst_useranswer(sess_id, test_id, que_des, ans1,ans2,ans3,ans4,ans5,true_ans,your_ans) values ('".session_id()."', $tid,'$row[2]','$row[3]','$row[4]','$row[5]', '$row[6]','$row[7]','$row[8]','$ans')") or die(mysql_error());
                if($ans==$row[8])
                {
                            $_SESSION[trueans]=$_SESSION[trueans]+1;
                }
                echo "<h1 class=head1> Result</h1>";
                $_SESSION[qn]=$_SESSION[qn]+1;
                echo "<Table align=center><tr class=tot><td>Total Question<td> $_SESSION[qn]";
                echo "<tr class=tans><td>True Answer<td>".$_SESSION[trueans];
                $w=$_SESSION[qn]-$_SESSION[trueans];
                echo "<tr class=fans><td>Wrong Answer<td> ". $w;
                echo "</table>";
                mysql_query("insert into mst_result(login,test_id,test_date,score) values('$login',$tid,'".date("d/m/Y")."',$_SESSION[trueans])") or die(mysql_error()); 
                mysql_query("insert into mst_adminresult(login,test_id,score) values('$login',$tid,$_SESSION[trueans])")  or die(mysql_error());
                echo "<h1 align=center><a href=review.php> Review Question</a> </h1>";
                unset($_SESSION[qn]);
                unset($_SESSION[sid]);
                unset($_SESSION[tid]);
                unset($_SESSION[trueans]);
                exit;
        }