how to keep current select value after submit

[eluser]teddy[/eluser]
I have a select list and when I submit with the validation is false the select list is not keep select value before I had choosen and I must select value again. Beside above I am newbie ci and how to use form_dropdown in my code below. Thank you for reading my topic.

View

Code:

<select class="default" name="diadiem">
<option value="--">--</option>;
   &lt;?php  
      foreach($tinhthanhpho as $diadiem)
         {
               echo "<option value='".$diadiem['id']."' >".$diadiem['ten_tinh']."</option>";
                                }                      
     ?&gt;
</select>

My controller

Code:

function post()
  {
    
   $tinhthanhpho=$this->util_model->getTinhThanhPho();
   $data['tinhthanhpho']=$tinhthanhpho;  
  
  }

My model

Code:

function getTinhThanhPho()
  {
   $sql="select * from tbl_tinhthanhpho";

   $rs=$this->db->query($sql)->result_array();

   return $rs;
  }

[eluser]memVN[/eluser]
hi you

Code:

<select class="default" name="diadiem">
<option value="--">--</option>;
   &lt;?php  
      foreach($tinhthanhpho as $diadiem)
         {
               echo "<option value='".$diadiem['id']."' >".$diadiem['ten_tinh']."</option>";
                                }                      
     ?&gt;
</select>

Please change to

Code:

<select class="default" name="diadiem">
<option value="--">--</option>

    &lt;?php foreach($tinhthanhpho as $diadiem) : ?&gt;
          <option value="&lt;?=$diadiem['id']?&gt;" &lt;?php if(@$_POST['diadiem'] == $diadiem['id']) echo "selected=selected"; ?&gt;>&lt;?=$diadiem['ten_tinh']?&gt;</option>                    
    &lt;?php endforeach ?&gt;
</select>

[eluser]teddy[/eluser]
Thank you for your help, it's work.
godless to you

[eluser]teddy[/eluser]
mod please close topic