How to remove PHP to put a slash in a separate folder?

Question

htaccess

Hello!
Please help, I can't find a solution.
It is required for all files of the /forum/ directory with the php extension to remove php and put a slash.
That is, redirect all files https://www.site.ru/forum/forum12/topic2401.php to https://www.site.ru/forum/forum12/topic2401/ Found solutions for the entire site, but then all files are redirected , and I only need in this directory /forum/. There is no physical directory.

Answer 1

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_URI} ^/forum/.+\.php$ 
RewriteRule ^(.+)\.php /$1 [L]

Answer 2

mod_rewrite

Answer 3

Try this construction in .htaccess:

RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^/forum/(.*)$ /forum.php [L]

and in forum.php add a request handler.