add a secondary URL button based on profile field detection

[Arctic_wolf92]

I was wondering if you could tell me how to add a custom URL button to the post bit only if it detects a URL on the profile?

I added a if statement in the functions_post.php
I have also added a postbit_customlink to my templates with
<a href="{$post['fid4']}" target="_blank" class="postbutton">customlink</a>

As well have added {$post['fid4']} this to link to the profile its in my if statement.
On show thread.php I added postbit_customlink to the right of postbit_www

I'll add a pastebin link with my functions_post.php when I get home just curios if anyone might have a quick solution

---

So I had my santax wrong on my if statement in functions_post