populating drop down list and using the selected command to select item

OOOOOOOHHHHH THANK YOU THANK YOU THANK YOU!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!  A Major break through, this was stopping me from completing a whole load of pages,  I owe you a drink!!!!!!!

Hi thanks for the feed back,  I think the issue is with the if statement.

The value  $url_show ['stand_id'] is the individual value stored in the  table.  The drop down list value is also coming from the database and if  the form has not been submitted it will not be showing a $_POST.   So I  need it to be comparing against the ID coming from the list containing  the drop down items, this is being pulled from the database with

$stand_set = getall_stands();
while ($stands = mysql_fetch_array($stand_set))

so  the argument  would be $stands ['stand_id'] being compared with  $url_show ['stand_id'] and then selecting the $stands ['stand_id']

Without the benefit of seeing all the code it is a little tough to see if the logic is valid, but something like this should work:

                          <?php
                                $stand_set = getall_stands();                
                                while ($stands = mysql_fetch_array ($stand_set) ) {       
                                  if (isset($_POST['stand_id']) == $url_show ['stand_id']);
                            ?>
                                <select name="stand_id">
                                <option><?php echo [add your code]; ?></option>
                                <option><?php echo [add your code]; ?></option>
                                <option><?php echo [add your code]; ?></option>
                                </select>
                            <?php }?>