class Invitation extends Controller
{

protected $friend_list = array();protected $level = 1;//获取好友列表public function invite_friends_list($my_all_friends = null,$begin  = false){    $uid = \Auth::user()->id;    if(!$begin && empty($my_all_friends)){        $my_all_friends = InvitationRelation::select('user_id')->where('fuid' , $uid)->get()->toArray();        $this->friend_list[$uid] = $my_all_friends;        array_push($this->friend_list[$uid] , array('level'=>$this->level));    }    foreach($my_all_friends as $friend_id) {                if(! empty($friend_id)){            // Log::info('这是邀请好友的id:',$friend_id);            $my_all_friends = InvitationRelation::select('user_id')->where('fuid' , $friend_id)->get()->toArray();            // Log::info('层级:',$my_all_friends);            if(count($my_all_friends) > 0){                $this->level++;                $this->friend_list[$friend_id['user_id']] = $my_all_friends;                array_push($this->friend_list[$friend_id['user_id']] , array('level'=>$this->level));                try{                    $this->invite_friends_list($my_all_friends ,true);                } catch (\Exception $e) {                    return \Response::json(['status' => 'error', 'error_msg' => '获取失败'], 422);                }            }            continue;        }    }    return \Response::json($this->friend_list);}

}

结果:
{

"1": [    {        "user_id": 2    },    {        "user_id": 3    },    {        "user_id": 4    },    {        "level": 1    }],"2": [    {        "user_id": 5    },    {        "user_id": 6    },    {        "user_id": 7    },    {        "user_id": 8    },    {        "level": 2    }],"7": [    {        "user_id": 9    },    {        "user_id": 10    },    {        "user_id": 11    },    {        "level": 3    }],"8": [    {        "user_id": 12    },    {        "user_id": 13    },    {        "user_id": 14    },    {        "user_id": 15    },    {        "level": 4    }],"13": [    {        "user_id": 20    },    {        "user_id": 21    },    {        "user_id": 22    },    {        "user_id": 23    },    {        "level": 5    }],"15": [    {        "user_id": 16    },    {        "user_id": 17    },    {        "user_id": 18    },    {        "user_id": 19    },    {        "level": 6    }],"18": [    {        "user_id": 24    },    {        "user_id": 25    },    {        "user_id": 26    },    {        "user_id": 27    },    {        "user_id": 28    },    {        "level": 7    }]

}