如何在php/javascript中创建计时器和警报

我想做多项选择中的倒计时。我想一个一个地展示问题。但是，当我单击下一个问题的“下一步”时，时间是从10分钟开始，而不是继续

如何发出警报如果时间已过，将直接转到结果？
请帮忙，我是javascript的初学者

代码：

---

使用PHP在服务器端计算时间，并在pageload上发送给JS。JS仅显示倒计时，如果时间超过let form.submit（）

您不应该像这样在源HTML上发送正确的答案信息，用户可以查看源代码并查看正确的答案。
计时器将仅在JavaScript中完成，您发布的PHP代码几乎完全无关。至于计时器，
setTimeout
是可以使用的工具。@JeremyJStarcher也许你看不到PHP草堆中的Javascript指针，但他使用的是
setTimeout
@Barmar哦，我在那里看到了，但我认为他最初没有编写的操作剪切和粘贴代码，所以我想让他关注它。
<?php
error_reporting(0);

$randomizequestions ="yes";
$a = array(
1 => array(
   0 => "____ is a question that concerns the researchers who have been studying it.",
   1 => "Because the spotted owl’s survival",
   2 => "Whether the spotted owl can survive",
   3 => "Can the spotted owl’s survival",
   4 => "The spotted owl could survive",
   6 => 2
),
2 => array(
   0 => "Most shrubs should be fertilized early in the summer ____ late fertilizing can damage some plants.",
   1 => ". Only if",
   2 => "; in fact,",
   3 => ", which",
   4 => ": because",
   6 => 2
),
3 => array(
   0 => "In the eighth century, the calendar used in Europe was not as _____ used by the Mayans in Central America.",
   1 => "accurately as",
   2 => "accurate than",
   3 => "accurate as that",
   4 => "accurate that was",
   6 => 3
),
4 => array(
   0 => "_____ crude hydrocarbons into such products as gasoline and petrochemicals is at the heart of the petroleum industry.",
   1 => "Refine",
   2 => "Are refined",
   3 => "By refining",
   4 => "Refining",
   6 => 4
),
5 => array(
   0 => "We ____ visit Eric when we are in London.",
   1 => "ought  ",
   2 => "should  ",
   3 => "didn’t ought   ",
   4 => "ought to",
   6 => 2
),
6 => array(
   0 => "I hardly ever go swimming _______.",
   1 => "nowadays",
   2 => "soon",
   3 => "today",
   4 => "everydays",
   6 => 1
),
7 => array(
   0 => "Which word goes in the space? Can you look after the ___ rabbit while we are on holiday?",
   1 => "childrens’s  ",
   2 => "childrens’  ",
   3 => "children’s ",
   4 => "child",
   6 => 3
),
8 => array(
   0 => "The hummingbird’s agility in flight lets it ____ from flower to flower like an insect.",
   1 => "flit",
   2 => "flitting",
   3 => "to flit",
   4 => "flits",
   6 => 1
),
9 => array(
   0 => "We went to the cinema and we went out for a drink ___.",
   1 => "afterwards",
   2 => "after",
   3 => "then",
   4 => "and then",
   6 => 1

),
10 => array(
   0 => "Do ____ of you have any money I can borrow?",
   1 => "either  ",
   2 => "both  ",
   3 => "neither",
   4 => "Theres No Answer",
   6 => 1
),
11 => array(
   0 => "Justice Sandra Day O'connor was _____ to serve on the U.S Supreme Court.",
   1 => "the women who first",
   2 => "the first woman ",
   3 => "who the fisrt woman",
   4 => "the first and a woman",
   6 => 2
),
12 => array(
   0 => "North Carolina is well known not only for the Great Smoky Mountains National Park ____ for the Cherokee settlements",
   1 => "but also",
   2 => "also",
   3 => "because",
   4 => "because of",
   6 => 1
),
13 => array(
   0 => "Humans _____ by what holds objects together.",
   1 => "always fascinated",
   2 => "have always fascinated",
   3 => "always has been fascinated",
   4 => "have always been fascinated",
   6 => 4
),
14 => array(
   0 => "In eastern Canada _____ approaches two hundred inches in Quebec and Newfoundland.",
   1 => "where the seasonal rainfall",
   2 => "the seasonal rainfall",
   3 => "that the seasonal rainfall",
   4 => "the seasonal rainfall it",
   6 => 4
),
15 => array(
   0 => "Large, fast–moving trucks have been known to create blasts of wind _____ a motorcyclist.",
   1 => "can startle",
   2 => "can they startle",
   3 => "that can startle",
   4 => "are startling",
   6 => 3
),
);

$max=15;

$question=$_POST["question"] ;

if ($_POST["Randon"]==0){
        if($randomizequestions =="yes"){$randval = mt_rand(1,$max);}else{$randval=1;}
        $randval2 = $randval;
        }else{
        $randval=$_POST["Randon"];
        $randval2=$_POST["Randon"] + $question;
                if ($randval2>$max){
                $randval2=$randval2-$max;
                }
        }

$ok=$_POST["ok"] ;

if ($question==0){
        $question=0;
        $ok=0;
        $percentaje=0;
        }else{
        $percentaje= Round(100*$ok / $question);
        }

if ($persentaje == 100){
        $hasil="C2 Proficiency";
      }elseif ($persentaje > 80) {
        $hasil="C1 Advanced";
      }elseif ($persentaje > 60) {
        $hasil="B2 Upper Intermediate";
      }elseif ($persentaje > 50) {
        $hasil="B1 Intermediate";
      }elseif ($persentaje > 40) {
        $hasil="A2 Pre Intermediate";
      }elseif ($persentaje > 30) {
        $hasil="A2 Elementary";
      }else {
        $hasil="A1 Beginner";
      }    
?>



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function Goahead (number){
        if (document.percentaje.response.value==0){
                if (number==<?php print $a[$randval2][6] ; ?>){
                        document.percentaje.response.value=1
                        document.percentaje.question.value++
                        document.percentaje.ok.value++
                }else{
                        document.percentaje.response.value=1
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});
// -->
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                Tes ini tentang rammar dan vocabulary dan hasil dari tes ini akan membantu anda mengetahui level CEFR anda. Anda <b>tidak dapat melihat jawaban yang benar</b> pada tes ini. Anda harus menyelesaikan tes dalam 10 menit. Good Luck. <br><br>
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              <br><strong><?php print $question+1; ?>. </strong><?php print "<b>".$a[$randval2][0]."</b>"; ?>
                <br><input type="radio" name="option" value="1"  onClick="Goahead (1);"><?php print $a[$randval2][1] ; ?>
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                <br><br>
              </form>
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                <input style="font-family:Trebuchet ms; font-size:14.5px; width:80px; border:1px;" type="submit" value="Next">

              <br><br></form>
              </td></tr>
              <?php
              }else{
              ?>
              <tr><td align="center">
              The Quiz has finished<br>
              <br>Percentage of correct responses: <?php print $percentaje ; ?> %
              <br>Hasil: <?php print $hasil ?>
              <p><a href="<?php print $address; ?>">Restart</a>

              <?php } ?>

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