js extension of Date of Date into the specified format

// get the current time 
// Date of the extension, into the specified format Date String 
// month (M), day (D), h (H), minutes (m), seconds (S), quarterly (q ) may be 1-2 placeholder 
// years (y) may be 1-4 placeholder milliseconds (S) with only a placeholder (1-3 digits) 
a Date. = function prototype.Format (FMT) {// author: meizz 
    var O = { 
        "M +": this.getMonth () +. 1, January // 
        "d +": this.getDate () , // day 
        "H +": this.getHours (), // h 
        "m +": this.getMinutes () , // points 
        "s +": this.getSeconds () , // seconds 
        "q +": Math.floor (( this.getMonth () + 3) / 3), // quarter 
        "S": this.getMilliseconds () // ms 
    }; 
    IF (/(y+)/.test(fmt)) = fmt.replace FMT (the 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;
}

// 调用：
// var time1 = new Date().Format("yyyy-MM-dd");
var time2 = new Date().Format("yyyy-MM-dd HH:mm:ss");
$('.datetime-top-right').html(time2);