1. 定义一个契约(接口)

app\Contracts\SuperModuleContract.php

<?php

namespace App\Contracts;

interface SuperModuleContract

{

    //激活超能力,这里参数必须是array，这就是一个规范

    public function activate(array $target);

}

2. 一个实现这个接口的类

app\Services\FlyPower.php

<?php

namespace App\Services;

use App\Contracts\SuperModuleContract;

class FlyPower implements SuperModuleContract

{

   public function activate(array $target)

   {

        //..可以根据$target 参数进行一些操作

        $ability = 'fly ability';

        return $ability;

    }

}

3. 创建服务提供者

app\Providers\SuperPowerProvider.php

<?php

namespace App\Providers;

use Illuminate\Support\ServiceProvider;

use App\Services\FlyPower;

class SuperPowerProvider extends ServiceProvider

{

    public function boot()

    {

        //

    }

    public function register()

    {

        //singleton绑定单例

        //如何使用:App::make('fly_power')方法时调用

        $this->app->singleton('fly_power',function(){

            return new FlyPower();

        });

        //bind绑定实例到接口以便依赖注入

        // 如何使用:在类构造方法中实例化，并指定接口类型

        $this->app->bind('App\Contracts\SuperModuleContract',function(){

            return new FlyPower();

        });

    }

}

4. 注册服务提供者

配置文件config/app.php的providers数组中：

'providers' => [

    //其他服务提供者

    App\Providers\SuperPowerProvider::class,

],

5. 创建facades

app\Facades\FlyPower.php

<?php

namespace App\Facades;

use Illuminate\Support\Facades\Facade;

class  FlyPower extends Facade

{

    protected static function getFacadeAccessor()

    {

        return 'fly_power';

    }

}

6. 再然后需要到配置文件config/app.php中注册门面类别名：

'aliases' => [

    ...//其他门面类别名映射

    'FlyPower' => App\Facades\FlyPower::class,

],

7. 写一个控制器进行测试

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;

use App\Contracts\SuperModuleContract;

use App;

use FlyPower;

class TestController extends Controller

{

    protected $superower;

    public function __construct(SuperModuleContract $super_power)

    {

        $this->super_power = $super_power;

    }

    public function getPower(Request $request){

        //实现超人的几种方式

        # 使用make方式

        $superman1 = App::make('fly_power')->activate(array());

        # 使用facades

        $superman2 = FlyPower::activate(array());

        # 构造函数，类型提示，依赖注入

        $superman3 = $this->super_power->activate(array());

        dd($superman1, $superman2, $superman3);

    }

}

结果：

"fly ability"

"fly ability"

"fly ability"

证明三个超人类都实现了。

8. 进一步分析

当有超人有多种超能力的时候怎么办

8.1 定义一个获取超能力的接口

app\Contracts\GetPowerContract.php

<?php

namespace App\Contracts;

interface GetPowerContract

{

    public function init();

}

8.2 一个实现获取超能力接口的类

app\Services\GetPower.php

<?php

namespace App\Services;

use App\Contracts\GetPowerContract;

use App;

class GetPower implements GetPowerContract

{

    public function init()

    {

        $config = config('power');

        $ability = $config['ability'];

        $ability = App::make($ability);

        return $ability;

    }

}

8.3 创建配置文件

app\config\power.php

<?php

return [

    'ability' => 'fly_power',

];

8.4 增加一个超能力类，需要实现超能力接口

app\Services\ShotPower.php

<?php

namespace App\Services;

use App\Contracts\SuperModuleContract;

class ShotPower implements SuperModuleContract

{

   public function activate(array $target)

   {

        //..可以根据$target 参数进行一些操作

        $ability = 'shot ability';

        return $ability;

    }

}

8.5 修改服务提供器

app\Providers\SuperPowerProvider.php

<?php

namespace App\Providers;

use Illuminate\Support\ServiceProvider;

use App\Services\FlyPower;

use App\Services\ShotPower;

use App\Services\GetPower;

class SuperPowerProvider extends ServiceProvider

{

    /**

     * Bootstrap the application services.

     *

     * @return void

     */

    public function boot()

    {

        //

    }

    /**

     * Register the application services.

     *

     * @return void

     */

    public function register()

    {

        //singleton绑定单例

        //如何使用:App::make('fly_power')方法时调用

        $this->app->singleton('fly_power',function(){

            return new FlyPower();

        }); 

        $this->app->singleton('shot_power',function(){

            return new ShotPower();

        }); 

        //bind绑定实例到接口以便依赖注入

        // 如何使用:在类构造方法中实例化，并指定接口类型

        $this->app->bind('App\Contracts\SuperModuleContract',function(){

            return new FlyPower();

        }); 

        $this->app->bind('App\Contracts\GetPowerContract',function(){

            //return new FlightPower();

            return new GetPower();

        });

    }

}

8.6 修改控制器测试代码