1     /** 2      *    日期-获取当月最后一天 3      *  @return int 4      */ 5     public function get_lastday() { 6         if($this->month==2) { 7             $lastday = $this->is_leapyear($this->year) ? 29 : 28; 8         } elseif($this->month==4 || $this->month==6 || $this->month==9 || $this->month==11) { 9             $lastday = 30;10         } else {11             $lastday = 31;12         }13         return $lastday;14     }15     16 17     18     /**19      *    日期-是否是闰年20      *  @return int21      */22     public function is_leapyear($year) {23         return date(‘L‘, $year);24     }