Question

class dbConnection {
public $pdo;
public function __construct() {
    $this->dbConnect();
}
public function dbConnect() {
    if((count($_POST) == 6)&&($_GET['a'] == "connect")) {
        $host = $_POST['host'];
        $port = $_POST['port'];
        $username = $_POST['username'];
        $password = $_POST['password'];
        $database = $_POST['database']; 
        try{
                $this->pdo = new PDO('mysql:host='.$host.';dbname='.$database.';port='.$port, $username, $password );
                echo 'Connection successful!';
                return $pdo;
        }
        catch(PDOException $e){
                echo 'Error: ' . $e->getMessage();
        }   
    }
}
}

class Group extends dbConnection { //Class for group, for ex. employe and employers.
public $name;  // Name of group
public $pdo;

public function __construct ($_name, $conn) {
$this->pdo = $conn;
$this->name = $_name;

}

public function getGroupList() {
    if(isset($this->pdo)) {
        try
        {
            $conn = $this->pdo;
          $conn ->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); //to catch exceptions

          $stmt = $pdo -> query('SELECT id, Name, Skills FROM '.$this->name); //sql query with group name
          $list = $stmt->fetchAll(PDO::FETCH_NUM); //fetch statement into array
          $stmt -> closeCursor();
          unset($stmt);
          return var_dump($list); //gives pure data
        }
        catch(PDOException $e) 
        {
          return 'There was some error: ' . $e->getMessage();
        }
    }
    else {
    $pdo;
    }
}

}

And execution:

$conn = new dbConnection;
$workers = new Group("workers", $conn);
$workers->getGroupList();

I get error:

Call to undefined method dbConnection::setAttribute()
on line:

$conn ->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); //to catch exceptions

I’m trying to solve that, I don’t know why php treats PDO object as a method. I don’t have any idea. And I have to write more letters.

Answer 1

$this->pdo in that context references a dbConnection object. Really, you should change the name to $this->conn or something similar for clarity.

To fix it, try:

$this->pdo->pdo->setAttribute();

or specifically, in the context of your code:

$conn->pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

However, it also seems you’re using Inheritance incorrectly.

Rather than passing a connection to the Group class, you should instead call the parent constructor so that it initializes properly, setting the value of pdo per its definition.

Try this:

class Group extends dbConnection { //Class for group, for ex. employe and employers.
    public $name;  // Name of group

    public function __construct ($_name) {
        $this->name = $_name;
        parent::__construct();
    }

From there, you can reference $this->pdo as it’s defined in dbConnection