让我们假设我是Adam，其角色为'ROLE_ADMIN'.我无法登录到前端.

lets assume that I'm user Adam with role 'ROLE_ADMIN'. I can't login to frontend.

您应该简单地将此代码添加到您的控制器中:

You should simple add this code to your controllers:

  if( $this->get('security.context')->isGranted('YOUR ROLE') )
            return new Response('yea!');

因此，如果要保护BackendController并允许使用"ROLE_ADMIN"登录用户，则应添加以下代码:

So, If you want to secure BackendController and let to login users with 'ROLE_ADMIN' you should add this code:

if( $this->get('security.context')->isGranted('ROLE_ADMIN') )
                return new Response('You are granted to see this site.');

此代码检查当前用户(我)是否具有角色ROLE_ADMIN.如果要检查用户是否具有'ROLE_ADMIN'并且没有'ROLE_USER'，只需添加:

This code checks if current user (me) has role ROLE_ADMIN. If you want to check if user has 'ROLE_ADMIN' AND doesn't have 'ROLE_USER' just add:

$security = $this->get('security.context');
if( $security->isGranted('ROLE_ADMIN') && !$security->isGranted('ROLE_USER') )
                    return new Response('You are not granted to see this site.');