javascript 格式化日期顯示

Date.prototype.format = function (format) //author: meizz {    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;}alert(new Date().format("yyyy-MM-dd"));alert(new Date("january 12 2008 11:12:30").format("yyyy-MM-dd hh:mm:ss"));