js 时间格式化

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;}var ddd = new Date();document.write (ddd.format('yy-MM-dd hh:mm:ss'));