What is Facades used in Laravel?

2019-01-18 01:11发布

问题:

I'm confused by the Facades offered by Laravel.

The Laravel documentation states:

Facades provide a "static" interface to classes that are available in the application's service container. Laravel ships with many facades which provide access to almost all of Laravel's features. Laravel facades serve as "static proxies" to underlying classes in the service container, providing the benefit of a terse, expressive syntax while maintaining more testability and flexibility than traditional static methods.

Please help me to understand:

  1. Why we really use use Illuminate\Support\Facades?
  2. How to create custom Facades ?

回答1:

Thanks sitepoint for sharing such informative and helpful knowledge about FACADE (FACADE in Laravel)

FACADE :- The Facade pattern is a software design pattern which is often used in object oriented programming. A facade is, in fact, a class wrapping a complex library to provide a simpler and more readable interface to it.

Facades in Laravel :- Facades provide a "static" interface to classes that are available in the application's service container. Laravel ships with many facades which provide access to almost all of Laravel's features. Laravel facades serve as "static proxies" to underlying classes in the service container, providing the benefit of a terse, expressive syntax while maintaining more testability and flexibility than traditional static methods.

How Facades Are implemented in Laravel

As you probably know, every service inside the container has a unique name. In a Laravel application, to access a service directly from the container, we can use the App::make() method or the app() helper function.

<?php

App::make('some_service')->methodName();

In Laravel, all services have a facade class. These facade classes extend the base Facade class which is part of the Illuminate/Support package. The only thing that they need to implement is the getFacadeAccessor method, which returns the service name inside the container.



回答2:

You can understand by this example

DB::table('table_name')->get();  

In this example, the DB is the facade. it is calling the table() static method on the DB facade.