PHP operates dates and strings to accurately calculate age

 $ni) {
      $not_birth = 1;
      $tmp = array($byear, $bmonth, $bday);
      list($byear, $bmonth, $bday) = array($year, $month, $day);
      list($year, $month, $day) = $tmp;
      list($bi, $ni) = array($ni, $bi);
    }
    $years = 0;
    while (($bi + 10000) <= $ni) {//先取岁数
      $bi += 10000;
      $years++;
      $byear++;
    }//得到岁数后 抛弃年
    list($m, $d) = $this->getMD(array($year, $month, $day), array($byear, $bmonth, $bday));
    return array('year' => $years, 'month' => $m, 'day' => $d, 'not_birth' => $not_birth);
  }
 
  /**
   * 只能用于一年内计算
   * @param type $ymd
   * @param type $bymd
   */
  public function getMD($ymd, $bymd) {
    list($y, $m, $d) = $ymd;
    list($by, $bm, $bd) = $bymd;
    if (($m . $d) < ($bm . $bd)) {
      $m +=12;
    }
    $month = 0;
    while ((($bm . $bd) + 100) <= ($m . $d)) {
      $bm++;
      $month++;
    }
    if ($bd <= $d) {//同处一个月
      $day = $d - $bd;
    } else {//少一个月
      $mdays = $bm > 12 ? $this->_getMothDay( ++$by, $bm - 12) : $this->_getMothDay($by, $bm);
      $day = $mdays - $bd + $d;
    }
    return array($month, $day);
  }
 
  private function _getMothDay($year, $month) {
    switch ($month) {
      case 1:
      case 3:
      case 5:
      case 7:
      case 8:
      case 10:
      case 12:
        $day = 31;
        break;
      case 2:
        $day = (intval($year % 4) ? 28 : 29); //能被4除尽的为29天其他28天
        break;
      default:
        $day = 30;
        break;
    }
    return $day;
  }
 
}
 
$cage = new Age();
$test = array(
  '1990-06-12',
  '1990-07-13',
  '1990-08-16',
  '1990-10-10',
  '1990-10-13',
  '1990-10-15',
  '1990-11-9',
  '1990-11-22',
  '2016-11-22',
  '2016-8-22',
  '2016-10-13',
);
echo date('Y-m-d');
echo '
';
foreach($test as $v){
  $tmp = $cage->calAge($v);
  echo $v , ':', $tmp['year'], '年', $tmp['month'],
 '月', $tmp['day'], '天', ';', $tmp['not_birth'], '
';
}
echo '
' ;
 
 
/*
  运行结果：
  2015-10-13
  1990-06-12:25年4月1天;0
  1990-07-13:25年3月0天;0
  1990-08-16:25年1月27天;0
  1990-10-10:25年0月3天;0
  1990-10-13:25年0月0天;0
  1990-10-15:24年11月28天;0
  1990-11-9:24年11月4天;0
  1990-11-22:24年10月21天;0
  2016-11-22:1年1月9天;1
  2016-8-22:0年10月9天;1
  2016-10-13:1年0月0天;1
 
 * 
 */