如果已在数据库中选择，则消除Selected选项...？

Question

I have a select box with options up to 20, for example, if option 5 or any other is selected and saved in a database in the specific column it won't show next time...
please guide me

<select class="form-control text-center" name="code" id="Code"    >
        <option value="">Select Code</option>
        <?php for($i = 1; $i <= 20; $i++){ ?>
            <option value="<?php echo $i; ?>"><?php echo $i; ?></option>
        <?php } ?>
</select>

Answer 1

Controller:

function index(){
   //below code should be in Model this is only for example
   $this->db->select('code');
   $query = $this->db->get_where('hr_levels', array('created_by' => $_SESSION['username']));
   if ($query->num_rows() > 0) {
        $code = $query->row('code');
   } else {
        $code = 0;
   }
   $option = array();
   for($i=1;$i<=20;$i++){
      if ($code != $i) {//no need to add if in view, just pass the data to view
         $option[$i] = $i;
      }
   }
   $data['options'] = $option;
   $this->load->view('option_view',$data);
}

view:

<select class="form-control text-center" name="code" id="Code"    >
    <option value="">Select Code</option>
     <?php foreach($options as $key => $value){ 
           <option value="<?php echo $key; ?>"><?php echo $value; ?></option>
     <?php } ?>
</select>