Javascript minuterie à UTC dépend de l'heure de l'ordinateur?

Question

Donc ce script (crédit à http://www.rmkwebdesign.com/Countdown_Timers/Repeating_Daily_Timer.html), est fondamentalement un compte à rebours quotidien Javascript. J'ai changé les variables getDate en getUTCDate, mais ce n'est pas encore UTC et cela dépend de l'horloge du client. Comment est-ce que je corrige ceci, et le fait de ne pas dépendre du temps d'ordinateur de côté de client ainsi le compte à rebours ne s'affichera pas incorrectement si le temps d'ordinateur de clients est faux ?? Merci.

Voici le code javascript:

<script type="text/javascript"> 

var current = "Test"; 

var startHour = 0; 

var startMinute = 0; 

var endHour = 23; 

var endMinute = 55; 

var tz = 0; 

var montharray=new Array("Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"); 

if (startMinute < 10){startMinute = "0" + startMinute;} 

function countdown() 
{ 
var today=new Date(); 
var todayy=today.getYear(); 
if (todayy < 1000) 
{todayy += 1900;} 

var todaym = today.getUTCMonth(); 
var todayd = today.getUTCDate(); 
var todayh = today.getUTCHours(); 
var todaymin = today.getUTCMinutes(); 
var todaysec = today.getUTCSeconds(); 

// add a zero in front of numbers<10 
todaymin = checkTime(todaymin); 
todaysec = checkTime(todaysec); 

var startString = parseInt(startHour + "" + startMinute + "00"); 

var nowString1 = montharray[todaym] + " " + todayd + ", " + todayy + " " + todayh + ":" + todaymin + ":" + todaysec; 
var nowString = Date.parse(nowString1) + (tz*1000*60*60); 
var nowTime = parseInt(todayh + "" + todaymin + "" + todaysec); 

var endString1 = (montharray[todaym] + " " + todayd + ", " + todayy + " " + endHour + ":" + endMinute); 
var endString = Date.parse(endString1) - (today.getTimezoneOffset() * (1000*60)); 

var dd = endString - nowString; 
var dday = Math.floor(dd/(60*60*1000*24)*1); 
var dhour = Math.floor((dd%(60*60*1000*24))/(60*60*1000)*1); 
var dmin = Math.floor(((dd%(60*60*1000*24))%(60*60*1000))/(60*1000)*1); 
var dsec = Math.floor((((dd%(60*60*1000*24))%(60*60*1000))%(60*1000))/1000*1); 

if ((dhour <= 0 && dmin <= 0 && dsec <= 0) || (nowTime < startString)) 
{ 
    document.getElementById('count2').innerHTML = current; 
    document.getElementById('count2').style.display = "inline"; 
    document.getElementById('count2').style.width = "390px"; 
    document.getElementById('dhour').style.display = "none"; 
    document.getElementById('dmin').style.display = "none"; 
    document.getElementById('dsec').style.display = "none"; 
    document.getElementById('hours').style.display = "none"; 
    document.getElementById('minutes').style.display = "none"; 
    document.getElementById('seconds').style.display = "none"; 
    setTimeout("countdown()",500); 
    return; 
} 

else 
{ 
    document.getElementById('count2').style.display = "none"; 
    document.getElementById('dhour').style.display = "inline"; 
    document.getElementById('dmin').style.display = "inline"; 
    document.getElementById('dsec').style.display = "inline"; 
    document.getElementById('hours').style.display = "inline"; 
    document.getElementById('minutes').style.display = "inline"; 
    document.getElementById('seconds').style.display = "inline"; 
    document.getElementById('dhour').innerHTML = dhour; 
    document.getElementById('dmin').innerHTML = dmin; 
    document.getElementById('dsec').innerHTML = dsec; 
    setTimeout("countdown()",500); 
} 

if (dhour < 2 || (dhour == 2 && dmin == 0 && dsec == 0)) 
{ 
    document.getElementById('dhour').style.color = "yellow"; 
    document.getElementById('dmin').style.color = "yellow"; 
    document.getElementById('dsec').style.color = "yellow"; 
} 

if (dhour < 1 || (dhour == 1 && dmin == 0 && dsec == 0)) 
{ 
    document.getElementById('dhour').style.color = "red"; 
    document.getElementById('dmin').style.color = "red"; 
    document.getElementById('dsec').style.color = "red"; 
} 
} 

function checkTime(i) 
{ 
if (i<10) 
    { 
    i="0" + i; 
    } 
return i; 
} 
</script> 

Answer 1

solution d'abord, je peux penser est que vous envoyez votre client le nombre de secondes la minuterie sera en place d'un horodatage, mais il pourrait être inexacts en raison de HTTP transfert de latence.