php日期所在月的第一天日期和最后一天/*** 日期所在月的第一天日期* @return int*/ public function getFirstDayOfMonth ($format = 'timestamp') {$day = $this->getPart('yy') . '-' . $this->getPart('mm') .
'-' . '01';if ($format=='timestamp') {$day = (int)$this->toTimeStamp($day);}return $day;}/*** 日期所在月的最后一天日期* @return int*/ public function getLastDayOfMonth ($format = 'timestamp') {$day = $this->getPart('yy') . '-' . $this->getPart('mm') .
'-' . $this->daysOfMonth();if ($format=='timestamp') {$day = (int)$this->toTimeStamp($day);}return $day;}