Baris 77 mengatakan bahawa bukan objek memanggil fungsi fetch(). Bolehkah seseorang menjelaskannya?

Question

. =>'root , ]; //Mod kes tunggal peribadi statik $instance = null; ; public $num1 = null; ///Sambungan pangkalan data persendirian $conn = null; this->connect(); } private function __clone() { // TODO: Laksanakan __clone() method } public static function getInstance($params=[]) { if(!self::$instance instanceof self){ self::$instance = new self($params); return self::$instance private function connect() { cuba { $dsn="{$this->dbConfig['db']}:host= {$; this->dbConfig['host']}; this->dbConfig['charset']}";                                                                               'Tangkap (pdoexception $ E) {DIE ('kegagalan sambungan pangkalan data'. $ e- & gt; getMessage ());} eksekutif fungsi awam ($ SQL) {$ NUM = $ ini- & gt; ; EC ($ sql); if($num>0) if(null !== $this->conn->lastInsertID()) { $this->insertID = $this->conn -> lastInsertID() ; Cetakan Mesej 'Operasi gagal '.$error[0].':'.$error[1].':'.$error[2];                                                                                                                                                  ambil ($sql)                                                     . $sql)-> fetch(PDO::FETCH_ASSOC); } public function fetchALl($sql) { return $this->conn->query($sql)->fetch(PDO::FETCH_ASSOC);;

Answer 1

Objek pdo tidak berjaya diperoleh, dan pengambilan kaedah ahli objek telah dipanggil untuk menyemak parameter sambungan.