ERROR in register.php - php

Question

Please help:
Fatal error: Call to a member function prepare() on a non-object in C:\wamp\www\ooploginreg\functions.php on line 14 Call Stack # Time Memory Function Location 1 0.0010 252552 {main}( ) ..\register.php:0 2 0.0020 265888 LoginRegistration->registerUser( ) ..\register.php:50
Codeline in functions.php:
<?php
require "config.php";
class LoginRegistration{
function _construct(){
$database = new DatabaseConnection();
}
public function registerUser($username, $password, $name, $email, $website){
global $pdo;
$query = $pdo->prepare("SELECT id FROM users WHERE username = ? AND email = ?");
$query->execute(array($username, $email));
$num = $query->rowCount;
if($num == 0){
$query = $pdo->prepare("INSERT INTO users (username, password, name, email, website)VALUES (?, ?, ?, ? ,?)");
$query->execute(array($username, $password, $name, $email, $website));
return true;
}else{
return print "<span style='color:=#e53d37'>Error...username/email already used.</span>";
}
}
}
?>

Answer 1

It looks like you are calling $pdo before it is initialized.

Answer 2

You called database connection in constructor. But your var "pdo" already have value. Your PDO make some data before this class runs.
Just Use
$this->database = new DatabaseConnection();

Answer 3

You create the variable $database but never used it:
$database = new DatabaseConnection();
Problems
You never used the $database variable
It is bad practice to use global
It is bad practice to have your class depend on database object
Connection should be passed to constructor
Solution
Your class should be like this:
class LoginRegistration
{
private $pdo;
function __construct($database)
{
$this->pdo = $database;
}
public function registerUser($username, $password, $name, $email, $website)
{
$query = $this->pdo->prepare("SELECT id FROM users WHERE username = ? AND email = ?");
$query->execute(array($username, $email));
$num = $query->rowCount;
if ($num == 0) {
$query = $this->pdo->prepare("INSERT INTO users (username, password, name, email, website)VALUES (?, ?, ?, ? ,?)");
$query->execute(array($username, $password, $name, $email, $website));
return true;
} else {
return print "<span style='color:=#e53d37'>Error...username/email already used.</span>";
}
}
}
usage:
$database = new DatabaseConnection();
$login = new LoginRegistration($database);