php Laravel 控制器中的全局变量

Global variable in laravel controller

提问by Nixxx27

I want the $yearvariable to be available in all functions of my PagesController. I tried this code but I didn't succeed.

我希望该$year变量在我的PagesController. 我试过这段代码，但没有成功。

class PagesController extends Controller
{
    public function __construct()
    {
        $dt = Carbon::parse();
        $year = $dt->year;
    }

    public function index()
    {
        return view('pages.index');
    }

    public function about()
    {
        return view('pages.about', compact('year'));
    }

    public function create()
    {
        return view('pages.create', compact('year'));
    }
}

回答by Tim

1. Option: Use the AppServiceProvider

1. 选项：使用 AppServiceProvider

In this case $year is available to ALL views!

在这种情况下，所有视图都可以使用 $year！

<?php

namespace App\Providers;

use Carbon;

class AppServiceProvider extends ServiceProvider
{
    /**
     * Bootstrap any application services.
     *
     * @return void
     */
    public function boot()
    {
        view()->share('year', Carbon::parse()->year);
    }

    /**
     * Register the service provider.
     *
     * @return void
     */
    public function register()
    {
        //
    }
}

2. Option: Use a View Composer

2. 选项：使用View Composer

In this case, the variable is only available to the views where you need it.

在这种情况下，该变量仅可用于您需要它的视图。

Don't forget to add the newly created provider to config/app.php!

不要忘记将新创建的提供程序添加到config/app.php!

<?php

namespace App\Providers;

use Illuminate\Support\ServiceProvider;
use Carbon;

class ComposerServiceProvider extends ServiceProvider
{
    /**
     * Register bindings in the container.
     *
     * @return void
     */
    public function boot()
    {
        // Using Closure based composers...
        view()->composer('pages.*', function ($view) {
            $view->with('year', Carbon::parse()->year);
        });
    }

    /**
     * Register the service provider.
     *
     * @return void
     */
    public function register()
    {
        //
    }
}

3. Use Blades @inject-method

3.使用刀片@inject-method

Within the views that need the year you could inject a Carbon instance like this:

在需要年份的视图中，您可以像这样注入一个 Carbon 实例：

@inject('carbon', 'Carbon\Carbon')

{{ $carbon->parse()->year }}

回答by aldrin27

Try this:

尝试这个：

//give private declaration
private $year;
public function __construct()
{
    $dt = Carbon::parse();
    $this->year = $dt->year;
}

public function index()
{
    return view('pages.index');
}

public function about()
{
    $year = $this->year;
    return view('pages.about',compact('year') );
}

public function create()
{
     $year = $this->year;
    return view('pages.create',compact('year') );
}

回答by Viktor

You can create a global singleton within App::before event

您可以在 App::before 事件中创建一个全局单例

App::before(function($request) {
    App::singleton('customYear', function(){
        $dt = Carbon::parse();
        $customYear = $dt->year;
        return $customYear;
    });

    // If you use this line of code then it'll be available in any view
    View::share('customYear', app('customYear'));

    //To get the same data in any controller you may use:
    $customYear = app('customYear');
});