global variable in laravel - php

Question

In PHP, I used to define some variables in my header.php and use them in all my pages. How can I have something like that in Laravel?
I am not talking about View::share('xx', 'xx' );
Assume I want to have a variable which holds a number in it and I need this number inside all my controllers to calculate something.

Answer 1

Sounds like a good candidate for a configuration file.
Create a new one, let's call it calculations.php:
Laravel ~4ish:
app
config
calculations.php
Laravel 5,6,7+:
config
calculations.php
Then put stuff in the new config file:
<?php return [ 'some_key' => 42 ];
Then retrieve the config in your code somewhere (note the file name becomes a "namespace" of sorts for the config item):
echo Config::get('calculations.some_key'); // 42 in Laravel ~4
echo config('calculations.some_key'); // 42 in Laravel ~5,6,7+

Answer 2

Set a property on the BaseController, which should be located in your controllers directory.
Your controllers should extend the BaseController class and thus inherit its properties.

Answer 3

You could use View Composers
And instead of using the boot method described in the docs you could use:
public function boot()
{
// Using class based composers...
view()->composer(
'*', 'App\Http\ViewComposers\ProfileComposer'
);
// Using Closure based composers...
view()->composer('*', function ($view) {
});
}
That would render whatever variables you declare with
$view->with('yourVariableName', 'yourVariableValue');
to all the views in your app.
Here is a full example of how I used this in one of my projects.
app/Providers/ComposerServiceProvider.php
<?php
namespace App\Providers;
use Illuminate\Support\ServiceProvider;
class ComposerServiceProvider extends ServiceProvider
{
/**
* Bootstrap the application services.
*
* #return void
*/
public function boot()
{
view()->composer(
'*', 'App\Http\ViewComposers\UserComposer'
);
}
/**
* Register the application services.
*
* #return void
*/
public function register()
{
//
}
}
app/Http/ViewComposers/UserComposer.php
<?php
namespace App\Http\ViewComposers;
use Illuminate\Contracts\View\View;
use Illuminate\Contracts\Auth\Guard;
class UserComposer
{
protected $auth;
public function __construct(Guard $auth)
{
// Dependencies automatically resolved by service container...
$this->auth = $auth;
}
public function compose(View $view)
{
$view->with('loggedInUser', $this->auth->user());
}
}
Just remember that because you declared a new service provider it needs to be included in the 'providers' array in config/app.php

Answer 4

You can define them in your app\Http\Controllers\Controller.php , for example:
<?php
namespace App\Http\Controllers;
use Illuminate\Foundation\Auth\Access\AuthorizesRequests;
use Illuminate\Foundation\Bus\DispatchesJobs;
use Illuminate\Foundation\Validation\ValidatesRequests;
use Illuminate\Routing\Controller as BaseController;
class Controller extends BaseController
{
public $test = 'something';
use AuthorizesRequests, DispatchesJobs, ValidatesRequests;
}
Then afterwards in all of your controllers, you can access this property by doing:
$this->test;