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codice:
<html> 
<head> 
<title>Gestione legalizzazione</title>

<style type="text/css">
<!--
body {
	background-color: #000;
	background-image: url(immagini/sfondo.gif);
	background-repeat: yes-repeat;
	background-position: center center;
}
</style>

<style type="text/css">
<!-- 
table.bordo { 
       border: 1px solid #0033FF;
       }
-->
</style>

<style type="text/css">
.testa{ color:#FF0000;
       font-size:12pt;
       font-weight:bold;
       text-align:left;
}
</style>

<style type="text/css">
.etichetta{color:#0033FF;
       width:25%;
       font-size:16pt;
       text-align: left;
}
</style>

<style type="text/css">
.menu{	color:#0033FF;
       font-size:16pt;
       text-align: left;
}
</style>

<script LANGUAGE="JavaScript" type="text/javascript">
    today=new Date();
    y0=today.getFullYear();
</script>

<script language="javascript">
lista_firme= new Array();
</script>

</head>

<body>

<form name="find_ente" id="find_ente" action="" method="post" target="_self">

<script LANGUAGE="JavaScript" type="text/javascript">
function seleziona_ente(Ente,ID){
  nome_form = document.getElementById('form_name').value;
  var sel=opener.document[nome_form].elements[ID];
  for(var k=0;k<sel.options.length;k++){
    if(sel.options[k].value==Ente){
      sel.selectedIndex=k;
      break;
    }
  }
}
</script>

<script LANGUAGE="JavaScript" type="text/javascript">
function azzera_firme(ID){
  nome_form = document.getElementById('form_name').value;
  var sel=opener.document[nome_form].elements[ID];
  for(k=sel.options.length-1;k>=0;k--){
    sel.remove(k);
    }
}
</script>

<?php

function columnSort($unsorted, $column) { 
   $sorted = $unsorted; 
   for ($i=0; $i < sizeof($sorted)-1; $i++) { 
     for ($j=0; $j<sizeof($sorted)-1-$i; $j++) 
       if ($sorted[$j][$column] > $sorted[$j+1][$column]) { 
         $tmp = $sorted[$j]; 
         $sorted[$j] = $sorted[$j+1]; 
         $sorted[$j+1] = $tmp; 
     } 
   } 
   return $sorted; 
} 

include "connect.php";

?> 
<table width="80%" align="center" border="0" cellpadding="1" cellspacing="7">
<tr>
<td class="menu">
<p style="font-size: 16pt; text-align: center; color:#0033FF;">Ricerca ente
</span></p>
</td>
</tr>
</table>

<input type="hidden" name="id_name" id="id_name" value="<?=$_GET['id_name_pass']?>">

<input type="hidden" name="form_name" id="form_name" value="<?=$_GET['form_pass']?>">

<?php

if ($_GET['filtro_scelto_pass']!='') { 
$filtro_scelto = $_GET['filtro_scelto_pass'];
}
else
{
$filtro_scelto = $_POST['filtro_ricerca'];
}

if ($_POST['ente_scelto']!='') { 
$ente_scelto = $_POST['ente_scelto'];
}
else
{
$ente_scelto = '';
}

?>




<table class="bordo" width="90%" align="center" border="0" cellpadding="2" cellspacing="7">
<tr>
<td class="testa">
Filtro</td>
<td class="testa">
Ente</td>
</tr>

<tr>
<td class="menu">
<span style="color:#0033FF; text-align: right;"><input type="text" name="filtro_ricerca" id="filtro_ricerca" size="20" onChange="this.form.submit();">
</span>
</td>

<?php

if ($filtro_scelto=='') {
$filtro = " tab_ente.IDEnte <> ''";
}

if ($filtro_scelto!='') {
   ?>
   <script LANGUAGE="JavaScript" type="text/javascript">
           function Verifica_Filtro() { 
                var chiave = '<? echo $filtro_scelto ?>';
                document.find_ente.filtro_ricerca.value = chiave;
           } 
           Verifica_Filtro();
   </script>
   <?php
   $filtro = " tab_ente.Ente like '%$filtro_scelto%'";
}

$ricer="select * from tab_ente WHERE {$filtro} ORDER BY Ente";
$stringa_sql=$ricer;
$result = mysql_query($ricer) or die(mysql_error());
?>
<td class="menu">
<span style="color:#0033FF; text-align: right;"><select name="ente_scelto" id="ente_scelto" style="width: 300px" onChange="seleziona_ente(document.getElementById('ente_scelto').value,document.getElementById('id_name').value); azzera_firme('firma'); this.form.submit();">
<option value="" selected="selected">  </option>
<?php
while($row = mysql_fetch_array($result))
{
if ($ente_scelto!=''){ 
   if ($ente_scelto==$row['IDEnte']){ 
      echo "<option value=\"" . $row['IDEnte'] . "\" selected=\"selected\">" . $row['Ente'] . "</option>"; 
      } 
      else 
      { 
      echo "<option value=\"" . $row['IDEnte'] . "\">" . $row['Ente'] . "</option>"; 
   } 
} 
else 
{
echo "<option value=\"" . $row['IDEnte'] ."\">". $row['Ente'] . "</option>"; 
} 

} 
?> 
</select>
</span>
</td>
</tr></table>

<?php

$lista_firma[] = array('id' => '','firma' => ''); 

$query = "SELECT * FROM tab_firma WHERE tab_firma.IDEnte = '".$ente_scelto."' ORDER BY Cognome, Nome";
$res = mysql_query($query) or die(mysql_error());

while($row = mysql_fetch_array($res)) {
     $lista_firma[] = array('id' => $row['IDFirma'],'firma' => $row['Cognome'] . " " . $row['Nome']);  
} 

$lista_ordinata = columnSort($lista_firma, 'firma'); 

?> 

<script LANGUAGE="JavaScript" type="text/javascript">
function carica_firme(ID){

nome_form = document.getElementById('form_name').value;
var sel=opener.document[nome_form].elements[ID];


var idArray = new Array(); 
var firmaArray = new Array(); 
     
<?php  

$i=0;

foreach($lista_ordinata as $val):
        $i = $i+1; 
        ?>
        idArray[<?php echo $i ?>] = "<?php echo$ $val['id'] ?>";  
        firmaArray[<?php echo $i ?>] = "<?php echo $val['firma'] ?>"; 
<?php  
endforeach;

?>
with (sel)
     {
     for (i=1;i<idArray.length;i++) {

     try {
         sel.add(new Option(firmaArray[i],idArray[i]), null);
         }
     catch (ex)
         {
          sel.add(new Option(firmaArray[i],idArray[i]));
         }
     }
}

} 

carica_firme('firma');

</script> 

<?php 
mysql_close($conn_ele);
?> 

<p style="font-size: 16pt; text-align: center; color:#0033FF;"><input type="button" value="Chiudi" onclick="self.close();"> 
</p>

</form>  
</body>
</html>