چرا کد javascript تاریخ را یک روز جلوتر نشان می دهد ؟

[abi_designer]

سلام، خسته نباشید

من از این کد برای تاریخ و ساعت سایتم استفاده می کنم و تا چند وقت پیش مشکلی نداشت ولی الان تاریخش یک روز جلوتر نشون میده : مثلا امروز شنبه 18 خرداد 92 ولی الان زده 19 خرداد.

<script language="JavaScript"> <!-- var timerID = null; var timerRunning = false; function showtime() {     var now = new Date();     var hours = now.getHours(); 	var tm = " AM";  	if (hours == 12) { tm = " PM"; } 	 	if (hours < 12) { tm = " AM"; }  	if (hours > 12) { hours = hours - 12; tm = " PM"; }  	if (hours == 0) { tm = " AM"; hours = 12; } 	     var minutes = now.getMinutes();     var seconds = now.getSeconds();     var timeValue = "" + hours;     timeValue  += ((minutes < 10) ? ":0" : ":") + minutes;     timeValue  += ((seconds < 10) ? ":0" : ":") + seconds;     LocalTimer.innerHTML = timeValue + tm;     timerID = setTimeout("showtime()",1000);     timerRunning = true; } //-->         </script> <script type="text/javascript"> function showdate() {  week= new Array("يكشنبه","دوشنبه","سه شنبه","چهارشنبه","پنج‌شنبه","جمعه","شنبه")  months = new Array("فروردين","ارديبهشت","خرداد","تير","مرداد"," شهريور","مهر","آبان","آذر","دي","بهمن","اسفند ");  a = new Date();  d= a.getDay();  day= a.getDate()+1;  month = a.getMonth()+1;  year= a.getYear();   year = (year== 0)?2000:year;  (year<1000)? (year += 2000):true;   year -= ( (month < 3) || ((month == 3) && (day < 21)) )? 622:621;  year = year % 100;  switch (month) {  case 1: (day<21)? (month=10, day+=10):(month=11, day-=20); break;  case 2: (day<20)? (month=11, day+=11):(month=12, day-=19); break;  case 3: (day<21)? (month=12, day+=9):(month=1, day-=20); break;  case 4: (day<21)? (month=1, day+=11):(month=2, day-=20); break;  case 5:  case 6: (day<22)? (month-=3, day+=10):(month-=2, day-=21); break;  case 7:  case 8:  case 9: (day<23)? (month-=3, day+=9):(month-=2, day-=22); break;  case 10:(day<23)? (month=7, day+=8):(month=8, day-=22); break;  case 11:  case 12:(day<22)? (month-=3, day+=9):(month-=2, day-=21); break;  default: break;  }  document.write(''+week[d]+' '+day+' '+months[month-1]+' '+ year);  } </script>

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