php获取当月最后一天函数分享

/**
???? *??? 日期-获取当月最后一天
???? *? @return int
???? */
??? public function get_lastday() {
??????? if($this->month==2) {
??????????? $lastday = $this->is_leapyear($this->year) ? 29 : 28;
??????? } elseif($this->month==4 || $this->month==6 || $this->month==9 || $this->month==11) {
??????????? $lastday = 30;
??????? } else {
??????????? $lastday = 31;
??????? }
??????? return $lastday;
??? }
??? /**
???? *??? 日期-是否是闰年
???? *? @return int
???? */
??? public function is_leapyear($year) {
??????? return date('L',$year);
??? }