igfs/app/controllers/AnswerController.php

<?php
namespace app\controllers;


use app\models\Answer;
use app\models\Upvote;

class AnswerController {
    public function actionAddAnswer($answer,$question_id,$user_id)
    {
        return Answer::create(['answer'=>$answer,'question_id'=>$question_id,'user_id'=>$user_id]);
    }
    public static function actionUpvoteAnswer($answer_id,$user_id)
    {
        return Upvote::create(['answer_id'=>$answer_id,'user_id'=>$user_id]);
    }

    public function actionUpdateAnswer($answer_id,$new_answer)
    {
        $answer = Answer::find($answer_id);
        $answer->answer = $new_answer;
        return $answer->save();
    }

    public function actionViewAllAnswers(): void
    {
        foreach (Answer::all() as $answer)
        {
            echo $answer->answer . "<br>";
        }
    }
}