Fatal error: Call to undefined method Database::prepare() - php

Question

I have created a separate class for database and users.
Database.php
class Database{
private $db;
public function __construct(){
/*** mysql hostname ***/
$hostname = 'localhost';
/*** mysql username ***/
$username = 'username_web';
/*** mysql password ***/
$password = 'password_web';
try {
$this->db = new PDO("mysql:host=$hostname;dbname=kamadhenu_web", $username, $password);
/*** echo a message saying we have connected ***/
}
catch(PDOException $e)
{
echo $e->getMessage();
}
}
/*** Query Function ***/
public function query($sql)
{
return $this->db->query($sql);
}
}
Users.php
class Users{
private $db;
public function __construct($database) {
$this->db = $database;
}
public function login($username, $password)
{
$query=$this->db->prepare("SELECT `password`, `id` FROM `users` WHERE `username` = ?");
$query->bindValue(1, $username);
try{
$query->execute();
$data = $query->fetch();
$stored_password = $data['password'];
$id = $data['id'];
#hashing the supplied password and comparing it with the stored hashed password.
if($stored_password === sha1($password)){
return $id;
}else{
return false;
}
}catch(PDOException $e){
die($e->getMessage());
}
}
}
Here is my Login page with username and password.
login.php
include('database.php');
include('users.php');
$dbh= new Database();
$users= new Users($dbh);
if (isset($_POST['submit']))
{
$username= $_POST['username'];
$password= $_POST['password'];
$login = $users->login($username, $password);
if ($login === false) {
$errors[] = 'Sorry, that username/password is invalid';
}
else {
// username/password is correct and the login method of the $users object returns the user's id, which is stored in $login.
$_SESSION['id'] = $login; // The user's id is now set into the user's session in the form of $_SESSION['id']
#Redirect the user to home.php.
header('Location: list-updates.php');
exit();
}
}
When I execute I get an error:
Call to undefined method Database::prepare()

Answer 1

You create $dbh when you instantiate Database(), but instantiating the Database only returns an instance of your Database class, not your db connection. You should have a getDb to get your connection from database object:
$dbClass = new Database();
$dbh = $dbClass->getDb(); // here you get the connection
$users= new Users($dbh); // here you give to Users() the $dbh, that isn't your
// connection.. it's just Database class
Database construct only return an instance of your Database class, not your db connection
class Database{
private $db;
public function __construct(){
try {
$this->db = new PDO("mysql:host=$hostname;dbname=kamadhenu_web", $username, $password);
/*** echo a message saying we have connected ***/
}
catch(PDOException $e)
{
echo $e->getMessage();
}
}
public function getDb() {
if ($this->db instanceof PDO) {
return $this->db;
}
}
}

Answer 2

add the method "getmyDB" to database file
class Database
{
/* Properties */
private $conn;
private $dsn = 'mysql:dbname=test;host=127.0.0.1';
private $user = 'root';
private $password = '';
/* Creates database connection */
public
function __construct()
{
try
{
$this->conn = new PDO($this->dsn, $this->user, $this->password);
}
catch(PDOException $e)
{
print "Error!: " . $e->getMessage() . "";
die();
}
return $this->conn;
}
public function getmyDB()
{
if ($this->conn instanceof PDO)
{
return $this->conn;
}
}
}
and call it when you create the constructor in the file user.php
include "database.php";
class User
{
/* Properties */
private $conn;
/* Get database access */
public
function __construct()
{
$this->conn = new Database();
$this->conn = $this->conn->getmyDB();
}
/* Login a user */
public
function login()
{
$stmt = $this->conn->prepare("SELECT username, usermail FROM user");
if ($stmt->execute())
{
while ($rows = $stmt->fetch())
{
$fetch[] = $rows;
}
return $fetch;
}
else
{
return false;
}
}
}
and finally add test.php file
include "user.php";
$user = new User();
$list = $user->login();
foreach($list as $test)
{
echo $test["username"];
}

Answer 3

Your Database class does not extend PDO neither it does implement prepare method.
In order to access your PDO object, you must make it public and access like:
From User class:
$this->db->db->prepare();
The best way would be to extend the PDO class.