javascript alert without refreshing?

[sde]

there is a page that i'm validating server-side.

i am re-populating the form field values with the post data.

if errors are found, i print a javascript alert() with the error.

the problem is, upon pressing 'ok' to the javascript alert, the text in the form fields goes away.

is there anyway to prevent the javascript alert from refreshing the form?

[sammy]

Thats strange...I tried to replicate your error and my data was not erased.

PHP Code:

<?
if( $HTTP_POST_VARS['summ'] == "submitted"){
        print "submitted";
        $val = $HTTP_POST_VARS['sammyz'];
}
?>
<form name="sammy" action="index.php" method="post">
<input type="text" value="<?echo $val?>"name="sammyz" size="20">
<input type="hidden" name="summ" value="submitted">
<input type="checkbox" name="chekbox">
<input type="submit">
</form>
<?
function printEr(){
        print("
        <script type='text/javascript' language='javascript'>
        <!--
        alert('Error');
        //-->
        </script>
        ");
}
if( $HTTP_POST_VARS['chekbox'] ){
        printEr();
}

?>

please forgive the messy coding, i just wanted to test how the data could have been erased.
basically i have a form that if the check box is checked, it will alert and simulate an error, then populate the form with the users data. When i press OK, the data remains

[sde]

thanks for working that out sammy. i was doing weird header stuff that i didn't think about which was switching between 2 pages without me really seeing it. ( with php )

thanks.