Losing Form data

[Victor Garcia Aprea [MVP]]

Hi Matthew,

Changes made to your listbox items at the client-side won't be automatically
persisted to the server. You will need to write some additional code to make
this happen (ie. posting the list of items in a hidden-form field, parsing
it at the server and updating the Items collection accordingly).

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Victor Garcia Aprea
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"Matthew C" <dotnet@noveris.com> wrote in message
news:SYkKa.12090$C83.1180465@newsread1.prod.itd.ea rthlink.net...

> Hello All,
>
> I have two List Boxes on one page, one list box is a populated server-side
> from a data source, the other is initially empty. The page then allows

the

> user to move data from the first box to the second (empty) list box via a
> client-size JavaScript.
>
> Once the second box has data in it, the user submits/posts and a

server-side

> function attempts to read the data.
>
> PROBLEM: The data (in the second box) that is populated through the
> client-side JavaScript is not persistent and does not make it to the

server.

> The first box maintains its data through postings, but the second box

loses

> all data.
>
> Any help is greatly appreciated.
>
> cheers
>
> Matthew
>
>
>

[digihoo]

i am validating form data, but when i redirect the user back to the
form page to correct the errors, all of the data they entered has
disappeared.

Please Help.

Thanks

[Pedro]

digihoo wrote:

> i am validating form data, but when i redirect the user back to the
> form page to correct the errors, all of the data they entered has
> disappeared.

The browser only displays what you send.
If you want to send the same data a user submitted, you have to save it
between the form processing script and the script that outputs that
form. I'd do that with session variables:

<?php // form processing script
session_start();
if (isset($_POST['userdata']) {
validate_data($_POST); // define according to your needs
$_SESSION['userdata'] = $_POST['userdata'];
}
header('Location: form_output.php');
exit('Redirected <a href="form_output.php">here</a>.');
?>

and

<?php // form output script
session_start();
if (isset($_SESSION['userdata']) {
$useradata = $_SESSION['userdata'];
} else {
$userdata = ''; // or some other default value
}
?>
<form method="post" action="form_process.php">
<input type="text" name="userdata" value="<?php echo $userdata; ?>" />
<input type="submit">
</form>



Happy Coding :-)

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[digihoo]

i should have been more specific here. the form also loses its data if
the user just clicks the back button - without actually submitting the
data.

when they click forward to the form again, the data is also gone.

i was told that this is caused by a bug in IE 6, and to put:

header("Cache-control: private");

in the code before any HTML. however, this didn't solve the problem.

is there a way to prevent form data from disappearing, whether or not
it has been submitted into post variables?

Thanks