help with javascript function that selects all options in a <select multiple> on submit

I want all the options selected when the user clicks the submit button so that in PHP i can get all the values that were in the list without the user having to highlight them. <?php foreach ($_POST['right'] as $selectedOption) { echo $selectedOption."<br>"; } ?> <script> function selectAllOptions(obj) { if (!hasOptions(obj)) { return; } for (var i=0; i<[login to view URL]; i++) { [login to view URL][i].selected = true; } } </script> <form name='dealerform' id='dealerform' method=post action='[login to view URL]' onsubmit='selectAllOptions(right)'> Offices -------------------------------------------------------------------> Selected Offices<br /> <table border="0" cellpadding="3" cellspacing="0"><tr><td> <select multiple style='width: 277px;' size="20" name="left[]"> <?php $sql="select officeid,name from office where officeid not in (select officeid from office_dealer) order by name"; if (!$result = $mysqli->query($sql)) { echo "Error selecting offices"; exit; } while ($row = $result->fetch_assoc()) { echo "<option value='{$row['officeid']}'>{$row['name']}</option>"; } ?> </select></td> <td align="center" valign="middle"> <input type="Button" value="Add >>" style="width:100px" onClick="SelectMoveRows([login to view URL]['left[]'],[login to view URL]['right[]'])"><br><br> <input type="Button" value="<< Remove" style="width:100px" onClick="SelectMoveRows([login to view URL]['right[]'],[login to view URL]['left[]'])"></td><td> <select multiple style='width: 277px;' size="20" name="right[]"> </select></td></tr></table> <br /><br /><input type='submit' tabindex=999 value='Submit'> </form>