Date.prototype.format = function(format){   
 /*  
  * eg:format="YYYY-MM-dd hh:mm:ss";  
  */  
 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;   
}