Empty query result in new file - php

Question

I write script login php oop.
I created file Db.php method runQuery:
function runQuery($query) {
$this->last_query_result = $this->conn->query($query);
if (!$this->last_query_result) {
$this->setError("Nie udalo sie wykonac zapytania: " . $this->conn->error);
}
}
And in file login.php i created new method loginUser:
public function loginUser($login, $pass) {
$this->result = parent::runQuery("SELECT * FROM users WHERE name = '" . $login . "' AND pass='" . $pass . "'");
var_dump($this->result);
}
The problem is that the query returns NULL.
The entire file db.php
class DbUser {
private $conn;
private $host;
private $user;
private $pass;
private $base;
private $last_query_result;
function __construct($host, $user, $pass, $base) {
$this->host = $host;
$this->user = $user;
$this->pass = $pass;
$this->base = $base;
$this->connect();
}
public function setError($error) {
throw new Exception($error);
}
protected function connect() {
$this->conn = #new mysqli($this->host, $this->user, $this->pass, $this->base);
if ($this->conn->connect_errno) {
$this->setError("Nie udalo sie polaczyc z baza danych: " . $this->conn->connect_error);
}
}
function runQuery($query) {
$this->last_query_result = $this->conn->query($query);
if (!$this->last_query_result) {
$this->setError("Nie udalo sie wykonac zapytania: " . $this->conn->error);
}
}
function fullList() {
$return = array();
while (($row = mysqli_fetch_assoc($this->last_query_result)) !== NULL) {
$return[] = $row;
}
return $return;
}
}
And file login.php
//kalsa logowania uzytkownika
include 'db.php';
class login extends DbUser {
private $login;
private $pass;
private $result;
function __construct() {
parent::__construct('localhost', 'michal', 'saba9811', 'test');
}
public function loginUser($login, $pass) {
$this->result = parent::runQuery("SELECT * FROM users WHERE name = '" . $login . "' AND pass='" . $pass . "'");
var_dump($this->result);
}
}
try {
$login = $_POST['login'];
$pass = $_POST['pass'];
$log = new login();
$log->loginUser($login, $pass);
} catch (Exception $e) {
echo $e->getMessage();
}

Answer 1

Your runQuery()function doesn't return anything -
function runQuery($query) {
$this->last_query_result = $this->conn->query($query);
if (!$this->last_query_result) {
$this->setError("Nie udalo sie wykonac zapytania: " . $this->conn->error);
}
}
So when you try to assign the return value to another variable, it has nothing to assign:
$this->result = parent::runQuery("SELECT * FROM users WHERE name = '" . $login . "' AND pass='" . $pass . "'");
Fetch your query results from $this->last_query_result or refactor your code. Or just have runQuery() return $this->last_query_result, but that's a bit redundant.