js精确到秒的时间代码

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<title>原生js精确到秒的时间代码</title>

</head>

<body>

<p>本地时间：<span id=localtime></span></p>

<script type="text/javascript">

function showLocale(objD){

var str,colorhead,colorfoot;

var yy = objD.getYear();

if(yy<1900) yy = yy+1900;

var MM = objD.getMonth()+1;

if(MM<10) MM = '0' + MM;

var dd = objD.getDate();

if(dd<10) dd = '0' + dd;

var hh = objD.getHours();

if(hh<10) hh = '0' + hh;

var mm = objD.getMinutes();

if(mm<10) mm = '0' + mm;

var ss = objD.getSeconds();

if(ss<10) ss = '0' + ss;

var ww = objD.getDay();

if ( ww==0 ) colorhead="<font color="#000000">";

if ( ww > 0 && ww < 6 ) colorhead="<font color="#000000">";

if ( ww==6 ) colorhead="<font color="#000000">";

if (ww==0) ww="星期日";

if (ww==1) ww="星期一";

if (ww==2) ww="星期二";

if (ww==3) ww="星期三";

if (ww==4) ww="星期四";

if (ww==5) ww="星期五";

if (ww==6) ww="星期六";

colorfoot="</font>"

str = colorhead + yy + "-" + MM + "-" + dd + " " + hh + ":" + mm + ":" + ss + " " + ww + colorfoot;

return(str);

}

function tick(){

var today;

today = new Date();

document.getElementById("localtime").innerHTML = showLocale(today);

window.setTimeout("tick()", 1000);

}

tick();

</script>

</body>

</html>