If statement doesn't work in a function - php

Question

Not sure if this is a common problem or not, but I ran upon it. When trying to put a if/else statement into a function, it simple does not work. But when do the if/else without the function, it does work (So, I know that the if/else is correct).
I have 2 separate documents, Home.php and Functions.php here is what I have inside those files"
Home.php (the PHP)
<?php
$db = new PDO("mysql:host=localhost;dbname=TEST;charset=utf8","Xero","");
include("Functions.php");
menu();
?>
And then we have the Functions.php (the PHP)
<?php
$db = new PDO("mysql:host=localhost;dbname=TEST;charset=utf8","Xero","");
function menu() {
echo "
<div id='menu'>
<div id='user-menu'>
";
// Check AutoLogin-User then :
$getAutoUser = $db->prepare("SELECT * FROM `users-PHP_FNC` WHERE `ip`='" . $_SERVER['REMOTE_ADDR'] . "'");
$getAutoUser->execute();
if ($autoUser = $getAutoUser->fetch(PDO::FETCH_ASSOC)) {
echo "
" . $autoUser['user'] . "
";
}
// If no AutoLogin-User was found:
else {
echo "
Test
";
}
echo "
</div>
</div>
";
}
?>
Not sure why this doesn't work. Are you not allowed to have if/else statements in a PHP function?

Answer 1

Actually, you can be sure that if ... else statements work inside the scope of a function.
Therefore, the problem lies elsewhere... But there is another thing that you should do:
// Replace this
if ($autoUser = $getAutoUser->fetch(PDO::FETCH_ASSOC))
// By this
if ($autoUser == $getAutoUser->fetch(PDO::FETCH_ASSOC))
Why ?
Because when you say if ($something = $somethingElse) you tell PHP different things in a particular order:
1st => assign the current value of $somethingElse to $something
2nd => test if $something and $somethingElse share the same value
2nd becoming obviously true because of 1st.
To bypass the 1st step, simply use == in place of =.

Answer 2

$db is not in the function's scope. You would have to pass it in. I would make my code more like:
// connect.php - should be in a separate secure folder I'll call restricted
<?php
function db(){
return new PDO('mysql:host=localhost;dbname=TEST;charset=utf8', 'Xero', '');
}
?>
// index.php
<?php
include_once 'restricted/connect.php';
function menu(){
$db = db();
echo "<div id='menu'><div id='user-menu'>";
// Check AutoLogin-User then :
$getAutoUser = $db->prepare("SELECT * FROM `users-PHP_FNC` WHERE ip='{$_SERVER['REMOTE_ADDR']}'");
$getAutoUser->execute();
if($autoUser = $getAutoUser->fetch(PDO::FETCH_ASSOC)) {
echo $autoUser['user'];
}
else{
// If no AutoLogin-User was found:
echo 'Test';
}
echo '</div></div>';
}