PHP7/Laravel - 聲明，應該兼容

Question

目前面臨一個舊的 Laravel 項目的問題，我正在嘗試恢復和更新。 我們收到的錯誤是在 MessagesController 的第 11 行拋出，如下所示：“.../app/Http/Controllers/Administrator/MessagesController.php:11”

Declaration of 
App\Http\Controllers\Administrator\MessagesController::getUsername(Illuminate\Http\Request $request)
should be compatible with 
App\Http\Controllers\Controller::getUserName(?App\Http\Controllers\Request $request = NULL)

消息控制器：

namespace App\Http\Controllers\Members;

use App\Http\Controllers\Controller;
use App\Message;
use App\User;
use Illuminate\Http\Request;
use DB;
use Response;

class MessagesController extends Controller
{

    //trimmed for Stackoverflow

    public function getUsername(Request $request)
    {
        $term = $request->input('term');
        $results = array();

        $queries = DB::table('users')->where('username', 'LIKE', '%' . $term . '%')
            ->take(5)
            ->get();

        foreach ($queries as $query) {
            $results[] = [
                'id' => $query->id,
                'value' => $query->username
            ];
        }

        return Response::json($results);
    }
}

基本控制器：

namespace App\Http\Controllers;

use Illuminate\Foundation\Bus\DispatchesJobs;
use Illuminate\Routing\Controller as BaseController;
use Illuminate\Foundation\Validation\ValidatesRequests;
use Illuminate\Foundation\Auth\Access\AuthorizesRequests;
use Sentinel;

class Controller extends BaseController
{
    use AuthorizesRequests, DispatchesJobs, ValidatesRequests;

    protected function getUser()
    {
        $user = Sentinel::getUser();
        return $user;
    }

    protected function getUserName(Request $request = null)
    {
        return $this->getUser()->username ?? null;
    }

    protected function getUserID()
    {
        return $this->getUser()->id ?? null;
    }
}

Answer 1

你的父Controller沒有包含use Illuminate\\Http\\Request; .

其次，您的父 getUserName 方法將請求參數設置為可為空。 所以把你的MessagesController改成這個。

public function getUsername(?Request $request)
{

Answer 2

此錯誤也可能是由於控制器中具有相同名稱的方法所致。 例如，

    class Controller extends BaseController
{
    // use AuthorizesRequests, DispatchesJobs, ValidatesRequests;
    public function **contactUs**(?Request $request){
        (new MailingController())->**contactUs**($email, $full_name);
        return response()->json([
            'response'=>'Thank you for contacting us, we will reach back to you shourtly',
            'status'=>'200'
        ],
        200
        );
    }

}

經過多次調試，我通過重命名contactUs方法之一解決了這個問題。 很奇怪，但這解決了我的問題