Date.prototype.format = function(format){     var o = {     "M+" : this.getMonth()+1, //month     "d+" : this.getDate(),    //day     "h+" : this.getHours(),   //hour     "m+" : this.getMinutes(), //minute     "s+" : this.getSeconds(), //second     "q+" : Math.floor((this.getMonth()+3)/3),  //quarter     "S" : this.getMilliseconds() //millisecond     }     if(/(y+)/.test(format)) format=format.replace(RegExp.$1,     (this.getFullYear()+"").substr(4 - RegExp.$1.length));     for(var k in o)if(new RegExp("("+ k +")").test(format))     format = format.replace(RegExp.$1,     RegExp.$1.length==1 ? o[k] :     ("00"+ o[k]).substr((""+ o[k]).length));     return format; }

<script type="text/javascript"> setInterval(function(){     var time = new Date().format("hh:mm:ss");     var date = new Date().format("yyyy-MM-dd");     document.getElementById("Time").innerHTML=time;     document.getElementById("Date").innerHTML=date; },1000); </script> <div id="Date"></div> <div id="Time"></div>