I have a html form which has a select list box from which you can select multiple values because its multiple property is set to multiple. Consider form method is \'GET\'. T
You can use this code to retrieve values from multiple select combo box
HTML:
<form action="c3.php" method="post">
  <select name="ary[]" multiple="multiple">
    <option value="Option 1" >Option 1</option>
    <option value="Option 2">Option 2</option>
    <option value="Option 3">Option 3</option>
    <option value="Option 4">Option 4</option>
    <option value="Option 5">Option 5</option>
  </select>
  <input type="submit">
</form>
PHP:
<?php
$values = $_POST['ary'];
foreach ($values as $a){
    echo $a;
}
?>
                                                                        You could do like this too. It worked out for me.
<form action="ResultsDulith.php" id="intermediate" name="inputMachine[]" multiple="multiple" method="post">
    <select id="selectDuration" name="selectDuration[]" multiple="multiple"> 
        <option value="1 WEEK" >Last 1 Week</option>
        <option value="2 WEEK" >Last 2 Week </option>
        <option value="3 WEEK" >Last 3 Week</option>
         <option value="4 WEEK" >Last 4 Week</option>
          <option value="5 WEEK" >Last 5 Week</option>
           <option value="6 WEEK" >Last 6 Week</option>
    </select>
     <input type="submit"/> 
</form>
Then take the multiple selection from following PHP code below. It print the selected multiple values accordingly.
$shift=$_POST['selectDuration'];
print_r($shift);
                                                                        // CHANGE name="select2" TO name="select2[]" THEN
<?php
  $mySelection = $_GET['select2'];
  $nSelection = count($MySelection);
  for($i=0; $i < $nSelection; $i++)
   {
      $numberVal = $MySelection[$i];
        if ($numberVal == "11"){
         echo("Eleven"); 
         }
        else if ($numberVal == "12"){
         echo("Twelve"); 
         } 
         ...
         ...
    }
?>
                                                                        I fix my problem with javascript + HTML. First i check selected options and save its in a hidden field of my form:
for(i=0; i < form.select.options.length; i++)
   if (form.select.options[i].selected)
    form.hidden.value += form.select.options[i].value;
Next, i get by post that field and get all the string ;-) I hope it'll be work for somebody more. Thanks to all.
foreach ($_POST["select2"] as $selectedOption)
{    
    echo $selectedOption."\n";  
}
                                                                            <html>
<head>
<title>Untitled Document</title>
</head>
<body>
<form id="form1" name="form1" method="get" action="display.php">
  <table width="300" border="1">
    <tr>
      <td><label>Multiple Selection </label> </td>
      <td><select name="select2[]" size="3" multiple="multiple" tabindex="1">
        <option value="11">eleven</option>
        <option value="12">twelve</option>
        <option value="13">thirette</option>
        <option value="14">fourteen</option>
        <option value="15">fifteen</option>
        <option value="16">sixteen</option>
        <option value="17">seventeen</option>
        <option value="18">eighteen</option>
        <option value="19">nineteen</option>
        <option value="20">twenty</option>
      </select>
      </td>
    </tr>
    <tr>
      <td> </td>
      <td><input type="submit" name="Submit" value="Submit" tabindex="2" /></td>
    </tr>
  </table>
</form>
</body>
</html>
You can iterate it directly like this
foreach ($_GET['select2'] as $value)
    echo $value."\n";
or you can do it like this
$selectvalue=$_GET['select2'];
foreach ($selectvalue as $value)
    echo $value."\n";