JavaScript动态显示当前日期时间与星期几

<html> 
<head> 
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> 
<script type="text/javascript" src="/jquery/1.7.0/jquery.min.js"></script> 
<script type="text/javascript"> 
function currentTime(){ 
  var d=new Date(),str=''; 
  str+=d.getFullYear()+'年'; 
  str+=d.getMonth() + 1+'月'; 
  str+=d.getDate()+'日'; 
  str+=d.getHours()+'时'; 
  str+=d.getMinutes()+'分'; 
  str+= d.getSeconds()+'秒'; 
  return str; 
} 
setInterval(function(){$('#time').html(currentTime)},1000); 
</script> 
</head> 
<body> 
<div id="time"></div> 
</body> 
</html> 

function showTime(){ 
  var show_day=new Array('星期一','星期二','星期三','星期四','星期五','星期六','星期日'); 
  var time=new Date(); 
  var year=time.getYear(); 
  var month=time.getMonth(); 
  var date=time.getDate(); 
  var day=time.getDay(); 
  var hour=time.getHours(); 
  var minutes=time.getMinutes(); 
  var second=time.getSeconds(); 
  month<10?month='0'+month:month; 
  month=month+1; 
  hour<10?hour='0'+hour:hour; 
  minutes<10?minutes='0'+minutes:minutes; 
  second<10?second='0'+second:second; 
  var now_time='当前时间：'+year+'年'+month+'月'+date+'日'+' '+show_day[day-1]+' '+hour+':'+minutes+':'+second; 
  document.getElementById('showtime').innerHTML=now_time; 
  setTimeout("showTime();",1000); 
}