js将long日期格式转换为标准日期格式实现思路

<script language="javascript">

 //扩展Date的format方法

 Date.prototype.format = function(format) {

  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(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;

 }

 

 function getSmpFormatDate(date, isFull) {

  var pattern = "";

  if (isFull == true || isFull == undefined) {

   pattern = "yyyy-MM-dd hh:mm:ss";

  } else {

   pattern = "yyyy-MM-dd";

  }

  return getFormatDate(date, pattern);

 }

 

 function getSmpFormatNowDate(isFull) {

  return getSmpFormatDate(new Date(), isFull);

 }

 

 function getSmpFormatDateByLong(l, isFull) {

  return getSmpFormatDate(new Date(l), isFull);

 }

 

 function getFormatDateByLong(l, pattern) {

  return getFormatDate(new Date(l), pattern);

 }

 

 function getFormatDate(date, pattern) {

  if (date == undefined) {

   date = new Date();

  }

  if (pattern == undefined) {

   pattern = "yyyy-MM-dd hh:mm:ss";

  }

  return date.format(pattern);

 }

 //alert(getSmpFormatDate(new Date(1279849429000), true));

 //alert(getSmpFormatDate(new Date(1279849429000),false));

 //alert(getSmpFormatDateByLong(1279829423000, true));

 alert(getSmpFormatDateByLong(1279829423000, false));

 //alert(getFormatDateByLong(1279829423000, "yyyy-MM"));

 //alert(getFormatDate(new Date(1279829423000), "yy-MM"));

 //alert(getFormatDateByLong(1279849429000, "yyyy-MM hh:mm"));

</script>