我试图在按下按钮时使用Laravel（5.3）的destroy方法删除对象，但是我得到了MethodNotAllowedHttpException。

我的路线是

Route::delete('/admin/add/{id}', 'ItemController@destroy');

销毁方法是

public function destroy($id)
{
    $items = Item::where('id', $id)->get();
    foreach ($items as $item)
        $item->delete();
    return redirect('/admin/add');
}

我的表格是

<form action="{{ url('admin/add/'.$specific->id)}}" method="POST">
  {{ method_field('DELETE') }}
  {{ csrf_field() }}
  <div class="modal-footer no-border">
    <button type="submit" class="btn btn-primary">Delete</button>
  </div>
</form>

我检查了现有路由（php artisan route:list），删除路由显示：

DELETE   | admin/add/{id}   |          | App\Http\Controllers\ItemController@destroy

我得到的错误是

in RouteCollection.php line 218
at RouteCollection->methodNotAllowed(array('GET', 'HEAD', 'POST')) in RouteCollection.php line 205
at RouteCollection->getRouteForMethods(object(Request), array('GET', 'HEAD', 'POST')) in RouteCollection.php line 158
at RouteCollection->match(object(Request)) in Router.php line 766
at Router->findRoute(object(Request)) in Router.php line 621
at Router->dispatchToRoute(object(Request)) in Router.php line 607
at Router->dispatch(object(Request)) in Kernel.php line 268
at Kernel->Illuminate\Foundation\Http\{closure}(object(Request)) in Pipeline.php line 53
at Pipeline->Illuminate\Routing\{closure}(object(Request)) in CheckForMaintenanceMode.php line 46
at CheckForMaintenanceMode->handle(object(Request), object(Closure)) in Pipeline.php line 137
at Pipeline->Illuminate\Pipeline\{closure}(object(Request)) in Pipeline.php line 33
at Pipeline->Illuminate\Routing\{closure}(object(Request)) in Pipeline.php line 104
at Pipeline->then(object(Closure)) in Kernel.php line 150
at Kernel->sendRequestThroughRouter(object(Request)) in Kernel.php line 117
at Kernel->handle(object(Request)) in index.php line 53
at require('/Users/username/Sites/blades/public/index.php') in server.php line 133

根据Laravel路由说明，我正在使用表单并使用POST方法欺骗DELETE操作，但我仍然得到一个异常。任何帮助都将不胜感激。

注意：我在上一节中遵循了完整的示例https://laravel.com/docs/5.2/quickstart-intermediate，它在那里工作得非常好。我试图在另一个项目中重新创建它，这是导致问题的原因。