js时间格式

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;
}