js输出日期格式化

//日期格式化
        Date.prototype.Format = function(fmt) {
            var o = {
                "M+" : this.getMonth() + 1,
                "d+" : this.getDate(),
                "h+" : this.getHours(),
                "m+" : this.getMinutes(),
                "s+" : this.getSeconds(),
                "q+" : Math.floor((this.getMonth() + 3) / 3),
                "S" : this.getMilliseconds()
            };
            if (/(y+)/.test(fmt))
                fmt = fmt.replace(RegExp.$1, (this.getFullYear() + "").substr(4 - RegExp.$1.length));
            for (var k in o)
            if (new RegExp("(" + k + ")").test(fmt))
                fmt = fmt.replace(RegExp.$1, (RegExp.$1.length == 1) ? (o[k]) : (("00" + o[k]).substr(("" + o[k]).length)));
            return fmt;
        }
        //输出当前时间
        alert(new Date().Format("yyyy-MM-dd hh:mm:ss"));