Object couldn't be converted to string - php

Question

I'm getting this error message when trying to make a PDO connection:
Object of class dbConnection could not be converted to string in (line)
This is my code:
class dbConnection
{
protected $db_conn;
public $db_name = "todo";
public $db_user = "root";
public $db_pass = "";
public $db_host = "localhost";
function connect()
{
try {
$this->db_conn = new PDO("mysql:host=$this->$db_host;$this->db_name", $this->db_user, $this->db_pass);
return $this->db_conn;
}
catch (PDOException $e) {
return $e->getMessage();
}
}
}
The error is on the PDO line. Just in case, I insert the code where I access to the connect() method:
class ManageUsers
{
public $link;
function __construct()
{
$db_connection = new dbConnection();
$this->link = $db_connection->connect();
return $link;
}
function registerUsers($username, $password, $ip, $time, $date)
{
$query = $this->link->prepare("INSERT INTO users (Username, Password, ip, time1, date1) VALUES (?,?,?,?,?)");
$values = array($username, $password, $ip, $time, $date);
$query->execute($values);
$counts = $query->rowCount();
return $counts;
}
}
$users = new ManageUsers();
echo $users->registerUsers('bob', 'bob', '127.0.0.1', '16:55', '01/01/2015');

Answer 1

Change your connection setting to the following:
class dbConnection
{
protected $db_conn;
public $db_name = "todo";
public $db_user = "root";
public $db_pass = "";
public $db_host = "localhost";
function connect()
{
try {
$this->db_conn = new PDO("mysql:host={$this->db_host};{$this->db_name}", $this->db_user, $this->db_pass); //note that $this->$db_host was wrong
return $this->db_conn;
}
catch (PDOException $e) {
//handle exception here or throw $e and let PHP handle it
}
}
}
In addition, returning values in a constructor has no side-effects (and should be prosecuted by law).

Answer 2

Please follow below code , its tested on my server and running fine .
class Config
{
var $host = '';
var $user = '';
var $password = '';
var $database = '';
function Config()
{
$this->host = "localhost";
$this->user = "root";
$this->password = "";
$this->database = "test";
}
}
function Database()
{
$config = new Config();
$this->host = $config->host;
$this->user = $config->user;
$this->password = $config->password;
$this->database = $config->database;
}
function open()
{
//Connect to the MySQL server
$this->conn = new PDO('mysql:host='.$this->host.';dbname='.$this->database, $this->user,$this->password);
if (!$this->conn)
{
header("Location: error.html");
exit;
}
return true;
}