PHP file_exists method not working as expected - php

Question

I am trying to set the background of the html body dynamically. Basically if a file exists, use it, otherwise use the default. But it keeps using the default regardless of whether the file exists or not.
<style>
body
{
padding-top: 50px;
background-image: url("<?php
clearstatcache();
if(file_exists("/profile_img/".$profileData["ID"]."_bg.jpg"))
{
echo "/profile_img/".$profileData["ID"]."_bg.jpg?". rand(5, 15);
}
else
{
//echo "/profile_img/".$profileData["ID"]."_bg.jpg?". rand(5, 15);
echo "/profile_img/default.jpg?". rand(5, 15);
}
?>");
background-size: cover;
background-position: 50% 50%;
}
</style>
I have tried using the file (the commented line) and it works. I can not see why this doesn't work

Answer 1

Some issues:
Using / will be absolute, causing it to look in the root directory.
Always check vars are set before using.
All that's changing is the filename, so you can use a ternary, which will reduce alot of that code.
<?php
$background = isset($profileData["ID"]) && file_exists('./profile_img/'.$profileData["ID"].'_bg.jpg')
? $profileData["ID"].'_bg.jpg' : 'default.jpg';
?>
<style>
body {
padding-top: 50px;
background-image: url("/profile_img/<?= $background.'?_='.microtime(true) ?>");
background-size: cover;
background-position: 50% 50%;
}
</style>
If it's still not working:
Check the file actually exists.