javascript实现的Date日期格式化函数，实例代码如下：
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE>javascript下Date格式化函数---www.jb200.com</TITLE>
<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}|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);
}
});
};
function init(){
var date = new Date();
alert(date.format("MMMM dd,yyyy"));
}
</script>
</HEAD>
<BODY onload="init();">
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