concrete/src/Page/Page.php
public function getNextSubPageDisplayOrder()
    {
        $db = Database::connection();
        $max = $db->fetchColumn('select max(cDisplayOrder) from Pages where cParentID = ?', [$this->getCollectionID()]);

        return is_numeric($max) ? ($max + 1) : 0;
    }
public function getNextSubPageDisplayOrder()
    {
        $db = Database::connection();
        $max = $db->fetchColumn('select max(cDisplayOrder) from Pages where cParentID = ?', [$this->getCollectionID()]);

        return is_numeric($max) ? ($max + 1) : 0;
    }
public function getNextSubPageDisplayOrder ( ) { $ db = Database :: connection ( ) ; $ max = $ db -> fetchColumn ( 'select max(cDisplayOrder) from Pages where cParentID = ?' , [ $ this -> getCollectionID ( ) ] ) ; return is_numeric ( $ max ) ? ( $ max + 1 ) : 0 ; }
Get the next available display order of child pages.

@return int
Get the next available display order of child pages .