JavaScript如何格式化时间的方法

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 df=new SimpleDateFormat();//jsJava1.0需要使用DateFormat对象，不要弄错就是了
df.applyPattern("yyyy-MM-dd HH:mm:ss");
var date=new Date(2015,12,18,10,59,51);
var str=df.format(date);
document.write(str);//显示

G Era designator [url=]Text[/url] AD
y Year [url=]Year[/url] 1996; 96
M Month in year [url=]Month[/url] July; Jul; 07
w Week in year [url=]Number[/url] 27
W Week in month [url=]Number[/url] 2
D Day in year [url=]Number[/url] 1
d Day in month [url=]Number[/url] 10
F Day of week in month [url=]Number[/url] 2
E Day in week [url=]Text[/url] Tuesday; Tue
a Am/pm marker [url=]Text[/url] PM
H Hour in day (0-23) [url=]Number[/url] 0
k Hour in day (1-24) [url=]Number[/url] 24
K Hour in am/pm (0-11) [url=]Number[/url] 0
h Hour in am/pm (1-12) [url=]Number[/url] 12
m Minute in hour [url=]Number[/url] 30
s Second in minute [url=]Number[/url] 55
S Millisecond [url=]Number[/url] 978

// 对Date的扩展，将 Date 转化为指定格式的String 
// 月(M)、日(d)、小时(h)、分(m)、秒(s)、季度(q) 可以用 1-2 个占位符， 
// 年(y)可以用 1-4 个占位符，毫秒(S)只能用 1 个占位符(是 1-3 位的数字) 
// 例子： 
// (new Date()).Format("yyyy-MM-dd hh:mm:ss.S") ==> 2006-07-02 08:09:04.423 
// (new Date()).Format("yyyy-M-d h:m:s.S") ==> 2006-7-2 8:9:4.18 
Date.prototype.Format = function(fmt) 
{ //author: meizz 
 var o = { 
 "M+" : this.getMonth()+1, //月份 
 "d+" : this.getDate(), //日 
 "h+" : this.getHours(), //小时 
 "m+" : this.getMinutes(), //分 
 "s+" : this.getSeconds(), //秒 
 "q+" : Math.floor((this.getMonth()+3)/3), //季度 
 "S" : this.getMilliseconds() //毫秒 
 }; 
 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; 
}
var time1 = new Date().format("yyyy-MM-dd HH:mm:ss"); 
var time2 = new Date().format("yyyy-MM-dd");

<me:script language="javascript" type="text/javascript"><!--
 
/** 
 * 对Date的扩展，将 Date 转化为指定格式的String 
 * 月(M)、日(d)、12小时(h)、24小时(H)、分(m)、秒(s)、周(E)、季度(q) 可以用 1-2 个占位符 
 * 年(y)可以用 1-4 个占位符，毫秒(S)只能用 1 个占位符(是 1-3 位的数字) 
 * eg: 
 * (new Date()).pattern("yyyy-MM-dd hh:mm:ss.S") ==> 2006-07-02 08:09:04.423 
 * (new Date()).pattern("yyyy-MM-dd E HH:mm:ss") ==> 2009-03-10 二 20:09:04 
 * (new Date()).pattern("yyyy-MM-dd EE hh:mm:ss") ==> 2009-03-10 周二 08:09:04 
 * (new Date()).pattern("yyyy-MM-dd EEE hh:mm:ss") ==> 2009-03-10 星期二 08:09:04 
 * (new Date()).pattern("yyyy-M-d h:m:s.S") ==> 2006-7-2 8:9:4.18 
 */ 
Date.prototype.pattern=function(fmt) { 
 var o = { 
 "M+" : this.getMonth()+1, //月份 
 "d+" : this.getDate(), //日 
 "h+" : this.getHours()%12 == 0 ? 12 : this.getHours()%12, //小时 
 "H+" : this.getHours(), //小时 
 "m+" : this.getMinutes(), //分 
 "s+" : this.getSeconds(), //秒 
 "q+" : Math.floor((this.getMonth()+3)/3), //季度 
 "S" : this.getMilliseconds() //毫秒 
 }; 
 var week = { 
 "0" : "/u65e5", 
 "1" : "/u4e00", 
 "2" : "/u4e8c", 
 "3" : "/u4e09", 
 "4" : "/u56db", 
 "5" : "/u4e94", 
 "6" : "/u516d" 
 }; 
 if(/(y+)/.test(fmt)){ 
 fmt=fmt.replace(RegExp.$1, (this.getFullYear()+"").substr(4 - RegExp.$1.length)); 
 } 
 if(/(E+)/.test(fmt)){ 
 fmt=fmt.replace(RegExp.$1, ((RegExp.$1.length>1) ? (RegExp.$1.length>2 ? "/u661f/u671f" : "/u5468") : "")+week[this.getDay()+""]); 
 } 
 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; 
} 
 
var date = new Date(); 
window.alert(date.pattern("yyyy-MM-dd hh:mm:ss"));
// --></mce:script>

Date.prototype.format = function(mask) { 
 
 var d = this; 
 
 var zeroize = function (value, length) { 
 
 if (!length) length = 2; 
 
 value = String(value); 
 
 for (var i = 0, zeros = ''; i < (length - value.length); i++) { 
 
 zeros += '0'; 
 
 } 
 
 return zeros + value; 
 
 }; 
 
 return mask.replace(/"[^"]*"|'[^']*'|/b(?:d{1,4}|m{1,4}|yy(?:yy)?|([hHMstT])/1?|[lLZ])/b/g, function($0) { 
 
 switch($0) { 
 
 case 'd': return d.getDate(); 
 
 case 'dd': return zeroize(d.getDate()); 
 
 case 'ddd': return ['Sun','Mon','Tue','Wed','Thr','Fri','Sat'][d.getDay()]; 
 
 case 'dddd': return ['Sunday','Monday','Tuesday','Wednesday','Thursday','Friday','Saturday'][d.getDay()]; 
 
 case 'M': return d.getMonth() + 1; 
 
 case 'MM': return zeroize(d.getMonth() + 1); 
 
 case 'MMM': return ['Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec'][d.getMonth()]; 
 
 case 'MMMM': return ['January','February','March','April','May','June','July','August','September','October','November','December'][d.getMonth()]; 
 
 case 'yy': return String(d.getFullYear()).substr(2); 
 
 case 'yyyy': return d.getFullYear(); 
 
 case 'h': return d.getHours() % 12 || 12; 
 
 case 'hh': return zeroize(d.getHours() % 12 || 12); 
 
 case 'H': return d.getHours(); 
 
 case 'HH': return zeroize(d.getHours()); 
 
 case 'm': return d.getMinutes(); 
 
 case 'mm': return zeroize(d.getMinutes()); 
 
 case 's': return d.getSeconds(); 
 
 case 'ss': return zeroize(d.getSeconds()); 
 
 case 'l': return zeroize(d.getMilliseconds(), 3); 
 
 case 'L': var m = d.getMilliseconds(); 
 
 if (m > 99) m = Math.round(m / 10); 
 
 return zeroize(m); 
 
 case 'tt': return d.getHours() < 12 ? 'am' : 'pm'; 
 
 case 'TT': return d.getHours() < 12 ? 'AM' : 'PM'; 
 
 case 'Z': return d.toUTCString().match(/[A-Z]+$/); 
 
 // Return quoted strings with the surrounding quotes removed 
 
 default: return $0.substr(1, $0.length - 2); 
 
 } 
 
 }); 
 
};