Untitled

<?php
class DatabaseConnection {
    private $data, $sql, $conn, $host, $user, $pass, $dtbs;

    public function __construct($host, $user, $pass, $dtbs) {
        $this->host = $host;
        $this->user = $user;
        $this->pass = $pass;
        $this->dtbs = $dtbs;

        $this->conn = new mysqli($this->host, $this->user, $this->pass, $this->dtbs);
        if ($this->conn) {
            return $this->conn;
        } else {
            return false;
        }
    }

    public function query($sql, $data) {
        $this->data = $data;
        $this->sql = $sql;
        foreach ($data as $val) {
            if (strpos($this->sql, "'%i'") !== false || strpos($this->sql, "'%s'") !== false || strpos($this->sql, '"%i"') !== false || strpos($this->sql, '"%i"') !== false) {
                echo "SQL incorrect: There can't be any quotes around the parameters, because this function does that automaticly for you";
                exit();
            }
            $pos = strpos($this->sql, '%');
            $type = substr($this->sql, $pos, 2);
            if ($type == '%i') {
                if (is_int($val)) {
                    $this->sql = substr_replace($this->sql, $val, $pos, 2);
                } else {
                    echo "Parameter incorrect: Data is not an integer value";
                    exit();
                }
            } elseif ($type == '%s') {
                if (!is_int($val)) {
                    $this->sql = substr_replace($this->sql, "UNHEX('".bin2hex($val)."')", $pos, 2);
                } else {
                    echo "Parameter incorrect: Data is an integer value";
                    exit();
                }
            } else {
                echo "Parameter incorrect: Parameter %i for integer of %s for all other types of data";
                exit();
            }
        }

        $this->query = $this->conn->query($this->sql);
        return $this->query;

    }

    public function fetch($query) {
        return $query->fetch_assoc();
    }

    public function num_rows($query) {
        return $query->num_rows;
    }

}
?>

<?php
function __autoload($class){
  require('classes/' . strtolower($class) . '.class.php');
}
require('config.php');

$sql = new DatabaseConnection(DB_HOST, DB_USER, DB_PASS, DB_DTBS);
// The DB_xxxx constants are defined in config.php
?>
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>OOP - Object Orientated Programming</title>
</head>

<body>
<?php
$data = array(1, "Brian o'Reilly");
$query = $sql->query("SELECT * FROM users WHERE id = %i AND name = %s", $data);
if ($sql->num_rows($query) > 0) {
    while ($r = $sql->fetch($query)) {
        echo '<p>User ' . $r['name'] . ' has ID ' . $r['id'] . '</p>';
    }
} else {
    echo "<p>No results</p>";
}
?>
</body>
</html>