PHP OOP Login Script Help Needed

I'm writing a login script connecting to a PDO database. I've tested all input/outputs which work fine, but the actual selecting the user info from the database just doesn't work. I'm getting this error:
Fatal error: Call to undefined function getUser() in C:\xampp\htdocs\classes\loginclass.php on line 25

If I'm going about this the wrong way, please let me know as I'm just testing out more efficient ways of coding which is why I'm going for OOP rather than procedural.

index.php

<form method = "post" action="login.php">
   <label>Username</label><input type="text" name="username" id="username"><br />
   <label>Password</label><input type="password" name="password">
   <label>Password</label><input type="password" name="password2">
    <input type="submit" value="submit" name="submit">
</form>

PHP:

login.php

<?php
//Get data from the form
if (isset($_POST['submit'])){
    $username = $_POST['username'];
    $password = $_POST['password'];
    $password2 = $_POST['password2'];
}
//Include the class files
include "classes/loginclass.php";
//Instantiate the login function
$login = new Login();
//Set the password variables in the class to match the password passed from the form
$login->password = $password;
$login->password2 = $password2;
//Do it!
$login->logMeIn();
?>

PHP:

loginclass.php

<?php
class Login {
    //Declare variables
    public $username;
    public $password;
    public $password2;
    //Start login function
    function logMeIn(){
        //Check if passwords match
        if ($this->password == $this->password2){ //Passwords match, now include db.php and check if connection to database is successful
            include ("classes/db.php");
            if ($success = true){
                //echo "Connected to db via PDO...";
                include ("classes/userclass.php");
                $user = new getUser();
                $user->table = "users";
                $user->username = $username;
                $user->where = "username";
                //Do it!
                getUserDetails();
            }else {
                die("Not connected to the database");
            }
        }else {
            die("Your passwords do not match");
        }
    }
}
?>

PHP:

db.php

<?php
error_reporting(E_ALL);
ini_set('display_errors','1');
$username = "***";
$password = "***";
$id = 1;
try {
    $conn = new PDO('mysql:host=localhost;dbname=user', $username, $password);
    $success = true;
} catch(PDOException $e) {
    echo 'ERROR: ' . $e->getMessage();
}
?>

PHP:

userclass.php

<?php
class getUser {
    //Declare variables
    public $username;
    //Get user details from database
    function getUserDetails(){
        include ("classes/db.php");
        $stmt = $conn->prepare('SELECT * FROM $this->table WHERE $this->where = :$this->$username');
        $stmt->execute(array('username' => $username));
        while($row = $stmt->fetch()) {
            print_r($row);
        }
    }
}
?>

PHP:

 

I think you tried to call getUser method that does not exist in your getUser class. What you have there is just getUserDetails.

 

Replace
getUserDetails();
with
$user->getUserDetails();

 

Thanks, worked a treat.