3 Liste déroulante en chaine qui se Masque/Démasque les une aux autres

<form action="" method="post">

<table>

 <tr>

  <td>Country: </td>

  <td><select id="dhtmlgoodies_country" name="dhtmlgoodies_country" onchange="getStateList(this)">

   <option>Any</option>

    <?php

    $sql = 'SELECT * FROM pays ORDER BY pays_int';

    $query = mysql_query($sql) or die( 'Erreur' );

    while ( $g = mysql_fetch_array( $query ))

    {

     echo '<option value="'.$g['id_pays'].'">'.$g['pays_int'].'</option>';

     }

     ?>

   </select>

   </td>

  </tr>

  <tr id="dhtml_state" style="display:none">

    <td>State:</td>

    <td><select id="dhtmlgoodies_state" name="dhtmlgoodies_state" onchange="getCityList(this)"></select></td>

  </tr>

  <tr id="dhtml_city" style="display:none">

    <td>City: </td>

    <td><select id="dhtmlgoodies_city" name="dhtmlgoodies_city"></select></td>

  </tr>

</table>

</form>

function getStateList(sel)

{

 var countryCode = sel.options[sel.selectedIndex].value;

 var sel_state = document.getElementById('dhtmlgoodies_state');

 sel_state.options.length = 0;	// Empty city select box

 if(countryCode.length>0){

  document.getElementById('dhtml_state').style.display = "";

  var index = ajax.length;

  ajax[index] = new sack();

  ajax[index].requestFile = 'getCities.php?countryCode=' + countryCode;	// Specifying which file to get

  ajax[index].onCompletion = function(){ createState(index) };	// Specify function that will be executed after file has been found

  ajax[index].runAJAX();		// Execute AJAX function

 }

}

function getCityList(sel)

{

 var stateCode = sel.options[sel.selectedIndex].value;

 var sel_city = document.getElementById('dhtmlgoodies_city');

 sel_city.options.length = 0;	// Empty city select box

 if(stateCode.length>0){

  document.getElementById('dhtml_city').style.display = "";

  var index = ajax.length;

  ajax[index] = new sack();	

  ajax[index].requestFile = 'getCities.php?stateCode=' + stateCode;	// Specifying which file to get

  ajax[index].onCompletion = function(){ createCities(index) };	// Specify function that will be executed after file has been found

  ajax[index].runAJAX();		// Execute AJAX function

 }

}

function createState(index)

{

 var obj = document.getElementById('dhtmlgoodies_state');

 eval(ajax[index].response);	// Executing the response from Ajax as Javascript code	

}

function createCities(index)

{

 var obj = document.getElementById('dhtmlgoodies_city');

 eval(ajax[index].response);	// Executing the response from Ajax as Javascript code	

}