How to fix function to return multi array ci 3

You should init $ans array before the first (outer) foreach

PHP Code:

public function getexam_result($bode)
    {
        $ans=array();
        foreach($bode as $v)
        {
          $this->db->where('question_id',$v);
          $q=$this->db->get('answer_true');
          $rs=$q->result();
          //...
        }
        return $ans;
    }