function date_is_leap_year in Date 6.2

Same name and namespace in other branches

1. 5.2 date_php4/date_php4.inc \date_is_leap_year()
2. 6 date_php4/date_php4.inc \date_is_leap_year()

Returns true for a leap year, else FALSE. Works outside normal date range.

Parameters

int $year:

Return value

boolean

6 calls to date_is_leap_year()

date_calc_days_in_month in date_php4/date_php4_calc.inc

Find the number of days in the given month.

date_calc_gregorian_to_ISO in date_php4/date_php4_calc.inc

Converts from Gregorian Year-Month-Day to ISO Year-WeekNumber-WeekDay

date_calc_julian_date in date_php4/date_php4_calc.inc

Returns number of days since 31 December of year before given date.

date_php4.inc in date_php4/date_php4.inc

_date_getdate in date_php4/date_php4_lib.inc

Low-level function that returns the getdate() array for pre-1970 and post-2038 dates.

... See full list

File

date_php4/date_php4.inc, line 1057

Code

function date_is_leap_year($year) {
  if ($year < 1000) {
    return FALSE;
  }
  if ($year < 1582) {

    // pre Gregorio XIII - 1582
    return $year % 4 == 0;
  }
  else {

    // post Gregorio XIII - 1582
    return $year % 4 == 0 && $year % 100 != 0 || $year % 400 == 0;
  }
}