how to define a php config file that define constant and use it any where in project

Question

how to define a config file that i can use it any where whole project without include every where?

Answer 1

There are two ways,

1. define() : The constants you define using define method is available to the whole project.

   define('SITE_URL' , '/path/to/docroot/');
   echo SITE_URL;
   

2. Class constant : A class constant is available to the whole project.

   class MyConfig{
       const SITE_URL = '/path/to/docroot/';
   }
   echo MyConfig::SITE_URL;