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PHP Enhancing a Simple PHP Application Cleaning URLs with Rewrite Rules Introducing Rewrite Rules

Dan Neumann
PLUS
Dan Neumann
Courses Plus Student 10,318 Points
Posted by Dan Neumann
Dan Neumann
Courses Plus Student 10,318 Points

I'm really confused with php paths

Randy has written this code to access files in the same sub folder:

<?php 

require_once("../inc/config.php");
require_once(ROOT_PATH . "inc/products.php"); 

?>

Why does the first "require_once" access a file in the "inc" sub folder using "../" and the next uses the constant "ROOT_PATH"? Why not access files in the same folder the same way both times?

1 Answer

Ted Sumner
Ted Sumner
Courses Plus Student 17,967 Points

The first path is a relative path to the config.php, which contains certain defined constants. One of the constants is ROOT_PATH. The reason he does this is to make it easier to refactor the code. The ROOT_PATH constant is defined as the root path in any particular deployment. Here is an example of why it is nice.

My development environment is xampp. All the projects go in the htdocs folder. Since I am working on multiple projects, I put each of those in a subfolder. The root path is http://localhost/project. But when I deploy this site live the root path is the domain: http://project.com. All of my internal links that worked so nicely in my development environment are now broken because they are not in a subfolder anymore. I can go to my config folder and change my constant in one place to fix it.

I can also rearrange the internal structure and it is easier to fix the links.

Dan Neumann
Dan Neumann
Courses Plus Student 10,318 Points
Dan Neumann
Dan Neumann
Courses Plus Student 10,318 Points

Thanks Ted - This is beginning to make sense to me better.

Ted Sumner
Ted Sumner
Courses Plus Student 17,967 Points

The part that I struggled with was when to use ROOT_PATH and when to use BASE_URL. ROOT_PATH is used for the internal programming to describe where things are. BASE_URL is used to describe hyperlinked items.