Question

我有一个类Connection，它有一个对象$ db_connection（一个PDO对象）。然后我有一个具有Connection对象的Consultant连接。我想通过类Consultant的方法访问$ db_connection对象的方法。我试过这个：

$statement=$this->connection->db_connection->prepare($sqlQuery);

我有一个错误，说我试图获得非对象的属性。

连接类代码：

require('config.php');

class Connection{

    public $db_connection;

    public function __construct(){

        try{

            $this->db_connection = new PDO("mysql:host=".host."; dbname=".db_name,user,pass);
            $this->db_connection->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);
            $this->db_connection->exec("SET CHARACTER SET ".character_set);


        }
        catch(Exception $e){

            echo "<br>Error at line:".$e->getLine()."<br>";

        }   

    }

}

班级顾问代码：

require("Connection.php");

class Consultant{

    private $connection;

    function __construct(){

        $connection = new Connection();

    }

    public function getAllProducts(){


        $sqlQuery = "SELECT * FROM PRODUCTS;";

        $statement=$this->connection->db_connection->prepare($sqlQuery); //HERE IS THE ERROR LINE!!!!!!!!   

        $statement->execute(array());

        $result = $statement->fetchAll(PDO::FETCH_ASSOC);

        $statement->closeCursor();

        $this->db_connection = NULL;

        return $result;

    }

Answer 1

简而言之，在Consultant类中，您需要将$ connection作为类中的true属性。

class Consultant{

    private $connection;

    function __construct(){

   // $connection = new Connection();
   //**** Answer *****
   $this->connection = new Connection();

}

public function getAllProducts(){
    $sqlQuery = "SELECT * FROM PRODUCTS;";

    $statement=$this->connection->db_connection->prepare($sqlQuery);   

      ......
}

访问另一个对象内的对象的方法

1 个答案: