公历转换为波斯历

 

目中需要对波斯历的支持，在网上搜索了半天没有发现有javascript实现的函数。不过收获还是有的，做SourceForge.net里面找到了个Java实现，经改造后用javascript进行了封装。声明：算法的著作权属于原作者（Ghasem Kiani <ghasemkiani@yahoo.com>）！
有需要的朋友可以向我要Java源代码，也可以到http://www.sourceforge.net/去下载。
现提供javascript对日历转换的封装实现。
Calendar.js
波斯历转公历方法名称为：persianToGregorian(datetimeValue)
公历转波斯历方法名称为：calendarToPersian(datetimeValue)
datetimeValue的格式为：YYYY-MM-DD hh:mm:ss(2005-11-11 12:12:12)
---------------------------------------------------------
//The following variables is applied to Persian calendar convertion
var JULIAN_EPOCH_MILLIS = -210866803200000;
var ONE_DAY_MILLIS = 24 * 60* 60 * 1000;
var EPOCH = 1948321;

/**********************************************************
函数名称：calendarToPersian
函数说明：公历转换为波斯历
传入参数：datetimeValue:需要进行转换的公历日期值
返回：转换后的日历值
***********************************************************/
function calendarToPersian(datetimeValue)
{
var yearValue = datetimeValue.substring(0,4);//Year value
var monthValue = datetimeValue.substring(5,7)*1;//Month value
var dayValue =datetimeValue.substring(8,10)*1;//Day value
monthValue -= 1;
var persianDate = getPersianDay(yearValue,monthValue,dayValue);
persianDate.month += 1;
persianDate.month = persianDate.month.toString().length==1?"0"+persianDate.month:persianDate.month;
persianDate.day = persianDate.day.toString().length==1?"0"+persianDate.day:persianDate.day;

return persianDate.year+"-"+persianDate.month+"-"+persianDate.day+" "+datetimeValue.substring(11,datetimeValue.length);
}
/**********************************************************
函数名称：persianToGregorian
函数说明：转换波斯历为公历
传入参数：datetimeValue:需要进行转换的波斯历日期值
返回：转换后的日历值
***********************************************************/
function persianToGregorian(datetimeValue)
{
var persiaYear = datetimeValue.substring(0,4)*1;//Year value
var persiaMonth = datetimeValue.substring(5,7)*1;//Month value
var persiaDay =datetimeValue.substring(8,10)*1;//Day value
persiaMonth -= 1;
var julianDay = setJulianDay(pj(persiaYear > 0 ? persiaYear: persiaYear + 1, persiaMonth, persiaDay));
julianDay.month = julianDay.month.toString().length==1?"0"+julianDay.month:julianDay.month;
julianDay.day = julianDay.day.toString().length==1?"0"+julianDay.day:julianDay.day;
return julianDay.year+"-"+julianDay.month+"-"+julianDay.day+" "+datetimeValue.substring(11,datetimeValue.length);
}
/**********************************************************
函数名称：getPersianDay
函数说明：根据输入的日期获得Persia日期值
传入参数：year,month,day
返回：转换后的日历值
***********************************************************/
function getPersianDay(year,month,day)
{
var julianDay = getJulianDay(year,month,day);
var r = jp(julianDay);
var y1 = y(r);
var m1 = m(r);
var d1 = d(r);
y1 = y1 > 0?y1:y1-1;
var persiaDate = new Object();
persiaDate.year  = y1;
persiaDate.month = m1;
persiaDate.day = d1;
return persiaDate;
}
/**********************************************************
函数名称：getJulianDay
函数说明：根据输入的日期获得公历日期值
传入参数：year,month,day
返回：转换后的日历值
***********************************************************/
function getJulianDay(year,month,day)
{
return div(new Date(year,month,day,8,1,1) - JULIAN_EPOCH_MILLIS, ONE_DAY_MILLIS);
}
/**********************************************************
函数名称：setJulianDay
函数说明：根据输入的日期获得公历日期值
传入参数：julianDay
返回：转换后的日历值
***********************************************************/
function setJulianDay(julianDay)
{
var current = new Date();
var year = current.getFullYear();
var month = current.getMonth()+1;
var day = current.getDate();

var datetimevalue = JULIAN_EPOCH_MILLIS + julianDay * ONE_DAY_MILLIS + mod(new Date(year,month,day,8,1,1) - JULIAN_EPOCH_MILLIS, ONE_DAY_MILLIS);
current = new Date(datetimevalue);
var julianDate = new Object();
julianDate.year  = current.getFullYear();
julianDate.month = eval(current.getMonth()+1);
julianDate.day = current.getDate();
return julianDate;
}
/**********************************************************
函数名称：jp
函数说明：公历转换为波斯历
传入参数：julianDay
返回：转换后的日历值
***********************************************************/
function jp(j)
{
var a = j - pj(475, 0, 1);
var b = div(a, 1029983);
var c = mod(a, 1029983);
var d = c != 1029982? div(2816 * c + 1031337, 1028522): 2820;
var year = 474 + 2820 * b + d;
var f = (1 + j) - pj(year, 0, 1);
var month = f > 186? Math.ceil((f - 6) / 30) - 1: Math.ceil(f / 31) - 1;
var day = j - (pj(year, month, 1) - 1);
return (year << 16) | (month << 8) | day;
}
/**********************************************************
函数名称：pj
函数说明：波斯历转换为公历
传入参数：y,m,d
返回：转换后的日历值
***********************************************************/
function pj(y, m, d)
{
var a = y - 474;
var b = mod(a, 2820) + 474;
return (EPOCH - 1) + 1029983 * div(a, 2820) + 365 * (b - 1) + div(682 * b - 110, 2816) + (m > 6? 30 * m + 6: 31 * m) + d;
}
function div(a,b)
{
return Math.floor(a / b);
}
function mod(a,b)
{
return (a - b * Math.floor(a / b));
}
function y(r)
{
return r>>16;
}
function m(r)
{
return (r & 0xff00) >> 8;
}
function d(r)
{
return (r & 0xff);