Fatalerror: Cannotaccessemptyproperty

Code integration is as follows: {code...}, the following error occurs: Fatalerror: CannotaccessemptypropertyinF: Apache2.2htdocsemectest. phponline9. The abstract problem of removing the base class remains. Environment: apache2.2php5.3.5 code integration is as follows:

  $db = MySQL::getIns();    }}class catModel extends Model{    protected $table = 'emec_cat';    public function addCat($date){      $sql = $this->db->Autoexpr($date);      return $this->db->qurey($sql);    }} class MySQL {        static protected $Ins;        protected $res;        static function getIns(){            if(self::$Ins instanceof self){                return self::$Ins;        }            self::$Ins = new MySQL();            return self::$Ins;        }        private function __construct(){            $this->res = 1;        }        protected function __destruct(){            mysql_close($link);        }}$date = array();$date['cat_name'] = $_POST['cat_name'];$date['parent_id'] = $_POST['parent_id'] + 0;$date['intro'] = $_POST['intro'];$catMode = new catModel();$catMode->addCat($date); ?>

:
Fatal error: Cannot access empty property in F:\Apache2.2\htdocs\emec\test.php on line 9
Remove the base classabstractThe problem persists.
Environment:
apache2.2 php5.3.5

Reply content:

Code integration is as follows:

  $db = MySQL::getIns();    }}class catModel extends Model{    protected $table = 'emec_cat';    public function addCat($date){      $sql = $this->db->Autoexpr($date);      return $this->db->qurey($sql);    }} class MySQL {        static protected $Ins;        protected $res;        static function getIns(){            if(self::$Ins instanceof self){                return self::$Ins;        }            self::$Ins = new MySQL();            return self::$Ins;        }        private function __construct(){            $this->res = 1;        }        protected function __destruct(){            mysql_close($link);        }}$date = array();$date['cat_name'] = $_POST['cat_name'];$date['parent_id'] = $_POST['parent_id'] + 0;$date['intro'] = $_POST['intro'];$catMode = new catModel();$catMode->addCat($date); ?>

:
Fatal error: Cannot access empty property in F:\Apache2.2\htdocs\emec\test.php on line 9
Remove the base classabstractThe problem persists.
Environment:
apache2.2 php5.3.5

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