CALCUL LE TEMPS ÉCOULÉ À PARTIR D'UNE DATE

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function setcountup(theyear,themonth,theday){ 
yr=theyear;mo=themonth;da=theday 
} 
 
setcountup(2000,7,13) 

var displaymessage="depuis l'ouverture de ce site" 
var countupwidth='95%' 
var countupheight='20px' 
var countupbgcolor='lightyellow' 
var opentags='<font face="Verdana"><small>' 
var closetags='</small></font>' 
var montharray=new Array("Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec") 
var crosscount='' 

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window.onload=start_countup 

function countup(){ 
var today=new Date() 
var todayy=today.getYear() 
if (todayy < 1000) 
todayy+=1900 
var todaym=today.getMonth() 
var todayd=today.getDate() 
var todayh=today.getHours() 
var todaymin=today.getMinutes() 
var todaysec=today.getSeconds() 
var todaystring=montharray[todaym]+" "+todayd+", "+todayy+" "+todayh+":"+todaymin+":"+todaysec 
paststring=montharray[mo-1]+" "+da+", "+yr 
dd=Date.parse(todaystring)-Date.parse(paststring) 
dday=Math.floor(dd/(60*60*1000*24)*1) 
dhour=Math.floor((dd%(60*60*1000*24))/(60*60*1000)*1) 
dmin=Math.floor(((dd%(60*60*1000*24))%(60*60*1000))/(60*1000)*1) 
dsec=Math.floor((((dd%(60*60*1000*24))%(60*60*1000))%(60*1000))/1000*1) 

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crosscount.innerHTML=opentags+dday+ " jours, "+dhour+" heures, "+dmin+" minutes, et "+dsec+" secondes "+displaymessage+closetags 

setTimeout("countup()",1000) 
} 
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