Laravel 5.1中定義一組路由不要被 CSRF 保護

參考文檔定義App\Http\Middleware\VerifyCsrfToken.php的$except也沒有解決post請求的問題。
奇怪的是備注掉app\Http\Kernel.php的$middleware中的\App\Http\Middleware\VerifyCsrfToken::class之后依然報錯MethodNotAllowedHttpException in RouteCollection.php line 218
路由定義如下：

Route::group(['prefix' => 'api/caplus'],function(){
    Route::resource('public', 'CaPlusPublicController');
    Route::get('/comments','CaPlusPublicController@comments') -> name('comments');
    Route::get('/wxLogin','CaPlusPublicController@wxLogin') -> name('wxLogin');
    Route::post('/postSubmit','CaPlusPublicController@postSubmit') -> name('postSubmit');
});

VerifyCsrfToken.php:

<?php

namespace App\Http\Middleware;

use Illuminate\Foundation\Http\Middleware\VerifyCsrfToken as BaseVerifier;

class VerifyCsrfToken extends BaseVerifier
{
    /**
     * The URIs that should be excluded from CSRF verification.
     *
     * @var array
     */
    protected $except = [
        'api/*'
    ];
}