Drupal 9: implementing custom functionality in PHP

Question

I would really appreciate it if somebody would give me some hints about implementing/inserting custom functionality into a drupal 9 page with PHP code. I am trying to write a PHP function that is generating a file based on some specific properties of Drupal users on a button click, and I do not know where to start. I am really confused. Is there an easy way to insert PHP code into a Drupal basic page? I am searching for solutions, but what I always find is custom modules where none of the given examples is working

Answer 1

I would recommend to you to start from the basics. If you need some custom code based on Users' information, you will need to create a custom module.

Try to watch tutorials from Drupalize.me https://drupalize.me/series/module-development-guide

Answer 2

you could start creating a new folder inside web/modules/custom/ with your module name. Something like: web/modules/custom/my_custom_module

You should need these files to start:

• my_custom_module.info.yml
• my_custom_module.routing.yml

---

my_custom_module.info.yml

name: my_custom_module
type: module
description: 'Defines my_custom_module functionality'
core_version_requirement: ^8 || ^9
package: Custom

my_custom_module.routing.yml

my_custom_module.hello_world:
  path: '/hello-world'
  defaults:
    _controller: '\Drupal\my_custom_module\Controller\MyCustomClass::helloWorld'
    _title: 'Display an Hello World'
  requirements:
    _access: 'TRUE'

src/Controller/MyCustomClass.php

Inside your custom module folder, create this structure of folders src/Controller/ and the name of the class you want, in this example is MyCustomClass.php We'll extend from ControllerBase and will be sufficient to allow us to create custom functionalities.

<?php

namespace Drupal\my_custom_module\Controller;

use Drupal\Core\Controller\ControllerBase;
use Symfony\Component\HttpFoundation\Response;

class MyCustomClass extends ControllerBase {

  public function helloWorld() {
    return new Response("Hello World");
  }
}

It could be a good point to start learning and developing.