getDaysBetween static method

int getDaysBetween(int ay, int am, int ad, int by, int bm, int bd,)

获取两个日期之间相差的天数（如果日期a比日期b小，天数为正，如果日期a比日期b大，天数为负）

@param ay 年a @param am 月a @param ad 日a @param by 年b @param bm 月b @param bd 日b @return 天数

Implementation

static int getDaysBetween(int ay, int am, int ad, int by, int bm, int bd) {
  int n;
  int days;
  int i;
  if (ay == by) {
    n = getDaysInYear(by, bm, bd) -
        getDaysInYear(ay, am, ad);
  } else if (ay > by) {
    days = getDaysOfYear(by) - getDaysInYear(by, bm, bd);
    for (i = by + 1; i < ay; i++) {
      days += getDaysOfYear(i);
    }
    days += getDaysInYear(ay, am, ad);
    n = -days;
  } else {
    days = getDaysOfYear(ay) - getDaysInYear(ay, am, ad);
    for (i = ay + 1; i < by; i++) {
      days += getDaysOfYear(i);
    }
    days += getDaysInYear(by, bm, bd);
    n = days;
  }
  return n;
}