Help dinamis dropdown

//dropdown pilih provinsi
        $data["options_provinces"] = array("" => "[pilih Propinsi]");
 
        $provinces = $this->provinces_model->getprovince()-> result();
            foreach($provinces as $row)
            {
                $data['options_provinces'][$row->province_id] = row->province;
            }
 
 
 
        //dropdown pilih kota      
          $data["options_location"] = array("" => "[pilih Kota]");         
          $location = $this->location->function get_all_city()-> result();    
            foreach($location as $row)
            {
                $data['options_location'][$row->id_location] = $row->city;
            }  

--model province--
 function getprovince()
      {
 
        return $this->db->get($this->table);
  }
 
--model location--
 function get_all_city() {
 
   return $this->db->get($this->table);
  }