Javascript 使用Java脚本的在线测验计时器

Javascript 使用Java脚本的在线测验计时器,javascript,timer,Javascript,Timer,我正在编写一个在线定时考试,为了让计时器运行,我正在使用JS!计时器启动、计算时间以及在计时器过期时提交考试的代码如下: <script> //Once the complete page is loaded the GIF image disappears and questions are displayed function StartTimer() { document.getElementById('Loading').style.display = "none

我正在编写一个在线定时考试,为了让计时器运行,我正在使用JS!计时器启动、计算时间以及在计时器过期时提交考试的代码如下:

<script>
 //Once the complete page is loaded the GIF image disappears and questions are displayed
function StartTimer() 
{
    document.getElementById('Loading').style.display = "none";
    document.getElementById('Loaded').style.display = "block";
    document.getElementById('1').style.display = "block";
    document.getElementById('qustn1').style.backgroundColor="#dd6e23";
}
    //Sets the Interval to the time 
var ct = setInterval("calculate_time()",100); // Start clock.
setTimeOut("submitForm()", <?php echo $time_limit; ?>);
function submitForm()
{
    document.getElementById("submit").submit();
}
function calculate_time()
{
    var end_time = "<?php echo $_SESSION["start_time"]; ?>"; // Get end time from session variable (total time in seconds).
    var dt = new Date(); // Create date object.
    var time_stamp = dt.getTime()/1000; // Get current minutes (converted to seconds).
    var total_time = end_time - Math.round(time_stamp); // Subtract current seconds from total seconds to get seconds remaining.
    var mins = Math.floor(total_time / 60); // Extract minutes from seconds remaining.
    var secs = total_time - (mins * 60); // Extract remainder seconds if any.
    if(secs < 10){secs = "0" + secs;} // Check if seconds are less than 10 and add a 0 in front.
    document.getElementById("txt").value = mins + ":" + secs; // Display remaining minutes and seconds.
    // Check for end of time, stop clock and display message.
    if(mins <= 0)
    {
        if(secs <= 0 || mins < 0)
        {
            clearInterval(ct);
            document.getElementById("txt").value = "0:00";
            submitForm();
        }
    }
}

//加载完整页面后,GIF图像将消失并显示问题
函数StartTimer()
{
document.getElementById('Loading').style.display=“无”;
document.getElementById('Loaded').style.display=“block”;
document.getElementById('1').style.display=“block”;
document.getElementById('qustn1').style.backgroundColor=“#dd6e23”;
}
//将间隔设置为时间
var ct=setInterval(“计算时间()”,100);//开始计时。
setTimeOut(“submitForm()”,);
函数submitForm()
{
document.getElementById(“提交”).submit();
}
函数计算时间()
{
var end_time=”“//从会话变量获取结束时间(总时间,以秒为单位)。
var dt=new Date();//创建日期对象。
var time_stamp=dt.getTime()/1000;//获取当前分钟数(转换为秒)。
var total_time=end_time-Math.round(time_stamp);//从总秒数中减去当前秒数,得到剩余秒数。
var mins=Math.floor(total_time/60);//从剩余秒数中提取分钟数。
var secs=总时间-(分钟*60);//提取剩余秒数(如果有)。
如果(secs<10){secs=“0”+secs;}//检查秒数是否小于10,并在前面添加一个0。
document.getElementById(“txt”).value=mins+:“+secs;//显示剩余的分钟和秒数。
//检查时间结束、停止时钟和显示消息。
若有(分钟),;
}
.....

但当我这样做时,我无法准确地执行代码。即使计时器达到0:00,也无法提交考试,相反,负计时器正在运行!!请帮帮我

问题在于第二个代码中变量ct的范围不正确。实际上,您应该将这个变量放在一个可用于*calculate_time*函数的上下文中

例如,您可以尝试以下代码,将变量ct移动到最外面的范围:

<body onload="StartTimer()">
......
    <script>
    .....
    var ct = null;
    function StartTimer() {
        document.getElementById('Loading').style.display = "none";
        document.getElementById('Loaded').style.display = "block";
        document.getElementById('1').style.display = "block";
        document.getElementById('qustn1').style.backgroundColor="#dd6e23";
        ct = setInterval("calculate_time()",100); // Start clock.
        setTimeOut("submitForm()", <?php echo $time_limit; ?>);
    }

    function submitForm() {
        document.getElementById("submit").submit();
    }
    function calculate_time() {
        var end_time = "<?php echo $_SESSION["start_time"]; ?>"; // Get end time from session variable (total time in seconds).
        var dt = new Date(); // Create date object.
        var time_stamp = dt.getTime()/1000; // Get current minutes (converted to seconds).
        var total_time = end_time - Math.round(time_stamp); // Subtract current seconds from total seconds to get seconds remaining.
        var mins = Math.floor(total_time / 60); // Extract minutes from seconds remaining.
        var secs = total_time - (mins * 60); // Extract remainder seconds if any.
        if(secs < 10){secs = "0" + secs;} // Check if seconds are less than 10 and add a 0 in front.
        document.getElementById("txt").value = mins + ":" + secs; // Display remaining minutes and seconds.
        // Check for end of time, stop clock and display message.
        if(mins <= 0) {
            if(secs <= 0 || mins < 0) {
                clearInterval(ct);
                document.getElementById("txt").value = "0:00";
                submitForm();
            }
        }
    }

    .....
    </script>
......
</body>

......
.....
var-ct=null;
函数StartTimer(){
document.getElementById('Loading').style.display=“无”;
document.getElementById('Loaded').style.display=“block”;
document.getElementById('1').style.display=“block”;
document.getElementById('qustn1').style.backgroundColor=“#dd6e23”;
ct=setInterval(“计算时间()”,100);//开始时钟。
setTimeOut(“submitForm()”,);
}
函数submitForm(){
document.getElementById(“提交”).submit();
}
函数计算时间(){
var end_time=”“//从会话变量获取结束时间(总时间,以秒为单位)。
var dt=new Date();//创建日期对象。
var time_stamp=dt.getTime()/1000;//获取当前分钟数(转换为秒)。
var total_time=end_time-Math.round(time_stamp);//从总秒数中减去当前秒数,得到剩余秒数。
var mins=Math.floor(total_time/60);//从剩余秒数中提取分钟数。
var secs=总时间-(分钟*60);//提取剩余秒数(如果有)。
如果(secs<10){secs=“0”+secs;}//检查秒数是否小于10,并在前面添加一个0。
document.getElementById(“txt”).value=mins+:“+secs;//显示剩余的分钟和秒数。
//检查时间结束、停止时钟和显示消息。

如果(分钟我在一个在线测验应用程序上工作,我必须实现计时器。 我创建了一个Javascript函数,在body-load时调用它

`< script language ="javascript" >
           var tim;       
           var min = '${sessionScope.min}';
           var sec = '${sessionScope.sec}';

        function customSubmit(someValue){  
         document.questionForm.minute.value = min;   
         document.questionForm.second.value = sec; 
         document.questionForm.submit();  
         }  

    function examTimer() {
        if (parseInt(sec) >0) {

            document.getElementById("showtime").innerHTML = "Time Remaining :"+min+" Minutes ," + sec+" Seconds";
            sec = parseInt(sec) - 1;                
            tim = setTimeout("examTimer()", 1000);
        }
        else {

            if (parseInt(min)==0 && parseInt(sec)==0){
                document.getElementById("showtime").innerHTML = "Time Remaining :"+min+" Minutes ," + sec+" Seconds";
                 alert("Time Up");
                 document.questionForm.minute.value=0;
                 document.questionForm.second.value=0;
                 document.questionForm.submit();

             }

            if (parseInt(sec) == 0) {               
                document.getElementById("showtime").innerHTML = "Time Remaining :"+min+" Minutes ," + sec+" Seconds";                   
                min = parseInt(min) - 1;
                sec=59;
                tim = setTimeout("examTimer()", 1000);
            }

        }
    }
< /script>
`
` 变量min和sec的值由sessionVariable设置,sessionVariable在会话中保存考试时间

这里提供了具有计时器功能的完整应用程序


谢谢@Mohammad Dashti
`< script language ="javascript" >
           var tim;       
           var min = '${sessionScope.min}';
           var sec = '${sessionScope.sec}';

        function customSubmit(someValue){  
         document.questionForm.minute.value = min;   
         document.questionForm.second.value = sec; 
         document.questionForm.submit();  
         }  

    function examTimer() {
        if (parseInt(sec) >0) {

            document.getElementById("showtime").innerHTML = "Time Remaining :"+min+" Minutes ," + sec+" Seconds";
            sec = parseInt(sec) - 1;                
            tim = setTimeout("examTimer()", 1000);
        }
        else {

            if (parseInt(min)==0 && parseInt(sec)==0){
                document.getElementById("showtime").innerHTML = "Time Remaining :"+min+" Minutes ," + sec+" Seconds";
                 alert("Time Up");
                 document.questionForm.minute.value=0;
                 document.questionForm.second.value=0;
                 document.questionForm.submit();

             }

            if (parseInt(sec) == 0) {               
                document.getElementById("showtime").innerHTML = "Time Remaining :"+min+" Minutes ," + sec+" Seconds";                   
                min = parseInt(min) - 1;
                sec=59;
                tim = setTimeout("examTimer()", 1000);
            }

        }
    }
< /script>