问：当您在浏览器中单击刷新时，如何防止倒数计时器重新启动
<div id="quiz-time-left"> </div>
<script type="text/javascript">
var total_seconds = 60*10 ;
var minutes = parseInt(total_seconds/60);
var seconds = parseInt(total_seconds%60);
function countDownTimer(){
if(seconds < 10){
seconds= "0"+ seconds ;
}if(minutes < 10){
minutes= "0"+ minutes ;
}
document.getElementById("quiz-time-left").innerHTML
= "Time Left :"+minutes+"minutes"+seconds+"seconds";
if(total_seconds <= 0){
setTimeout("document.quiz.submit()",1);
}else{
total_seconds = total_seconds -1 ;
minutes = parseInt(total_seconds/60);
seconds = parseInt(total_seconds%60);
setTimeout("countDownTimer()",1000);
}
}
setTimeout("countDownTimer()",1000);
function finishpage(){
alert("unload event detected!");
document.quiz.submit();
}
window.onbeforeunload= function() {
setTimeout('document.quiz.submit()',1);
}
</script>
答：根据您的代码，您正在使用total_seconds = 60 * 10进行初始化，并且在每次刷新后，total_seconds再次设置为恒定值。
您应该将最后一个计数器值存储在localStorage中，并使用更新后的localStorage值初始化total_seconds。
if（localStorage.getItem（“ total_seconds”））{
var total_seconds = localStorage.getItem（“ total_seconds”）;
}其他{
var total_seconds = 60 * 10;
}
var minutes = parseInt（total_seconds / 60）;
var seconds = parseInt（total_seconds％60）;
函数countDownTimer（）{
if（秒<10）{
seconds =“ 0” +秒；
} if（分钟<10）{
minutes =“ 0” +分钟；
}
document.getElementById（“ quiz-time-left”）。innerHTML =“剩余时间：” +分钟+“分钟” +秒+“秒”;
if（total_seconds <= 0）{
setTimeout（“ document.quiz.submit（）”，1）;
}其他{
total_seconds = total_seconds -1;
分钟= parseInt（total_seconds / 60）;
秒= parseInt（total_seconds％60）;
localStorage.setItem（“ total_seconds”，total_seconds）
setTimeout（“ countDownTimer（）”，1000）;
}
}
