aggiungere valore

[seokey]

right!

la select è in un altro file...

<script type="text/javascript">
function AjaxFunction(cat_id)
{
var httpxml;
try
  {
  // Firefox, Opera 8.0+, Safari
  httpxml=new XMLHttpRequest();
  }
catch (e)
  {
  // Internet Explorer
          try
                        {
                    httpxml=new ActiveXObject("Msxml2.XMLHTTP");
                    }
              catch (e)
                    {
                try
              {
              httpxml=new ActiveXObject("Microsoft.XMLHTTP");
              }
                catch (e)
              {
              alert("Your browser does not support AJAX!");
              return false;
              }
            }
  }
function stateck() 
    {
    if(httpxml.readyState==4)
      {

var myarray=eval(httpxml.responseText);
// Before adding new we must remove previously loaded elements
for(j=document.testform.subcat.options.length-1;j>=0;j--)
{
document.testform.subcat.remove(j);
}


for (i=0;i<myarray.length;i++)
{
var optn = document.createElement("OPTION");
optn.text = myarray[i];
//optn.value = myarray[i];
document.testform.subcat.options.add(optn);

} 

      }
    }
    var url="dd.php";
url=url+"?cat_id="+cat_id;
url=url+"&sid="+Math.random();
httpxml.onreadystatechange=stateck;
httpxml.open("GET",url,true);
httpxml.send(null);
  }
</script>

<form name="testform" method='POST' action='mainck.php'>

Categoria 
  <select name=cat onChange="AjaxFunction(this.value);">
<option value=''><-- Seleziona --></option>
<?php
require "config.php";// connection to database 
$q=mysql_query("select * from hcat_it ");
while($n=mysql_fetch_array($q)){
echo "<option value=$n[idcat]>$n[categoria]</option>";
}
}
?>
</select>

<select name=subcat>

</select>
<input name=ID type=hidden value=ID /><input type=submit value=CERCA>
</form>