Ajax form validation without caching - php

Question

I am building an inline code validation for a web form. With my current script, When a bad code is entered and it is being corrected (same length), POST data is not using the latest value. For example, I first enter "QFFE" and then correct it to "QFFF", but the latter is not stored in $_POST. See Firebug extract ("QFFF" passed but "QFFE" processed):
Here is the code (AJAX part):
var data = {};
$(document).ready(function() {
$('input[type="submit"]').on('click', function() {
resetErrors();
var url = 'process.php';
$.each($('form input, form select'), function(i, v) {
if (v.type !== 'submit') {
data[v.name] = v.value;
}
}); //end each
console.log(data);
$.ajax({
dataType: 'json',
type: 'POST',
url: url,
data: data,
cache: false,
success: function(resp) {
if (resp === true) {
//successful validation
alert("OK, processing with workflow...");
// $('form').submit();
return false;
} else {
$.each(resp, function(i, v) {
console.log(i + " => " + v); // view in console for error messages
var msg = '<label class="error" for="'+i+'">'+v+'</label>';
$('input[name="' + i + '"], select[name="' + i + '"]').addClass('inputTxtError').after(msg);
});
var keys = Object.keys(resp);
$('input[name="'+keys[0]+'"]').focus();
console.log('QD: error val');
}
return false;
},
error: function() {
console.log('there was a problem checking the fields');
}
});
return false;
});
});
function resetErrors() {
$('form input, form select').removeClass('inputTxtError');
$('label.error').remove();
}
And here my PHP script (process.php):
<?php
//List of accepted codes
$code_list = array("QWOLVE", "QFFF");
session_start();
if(isset($_POST)){
if (empty($_POST['promo_code'])) {
$_SESSION['errors']['promo_code'] = 'Please enter a promo code to access the beta site';
}elseif(! in_array($_POST['promo_code'], $code_list)){
$_SESSION['errors']['promo_code'] = $_POST['promo_code']." is not a valid code";
unset($_POST);
}
if(count($_SESSION['errors']) > 0){
//This is for ajax requests:
if(!empty($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest') {
echo json_encode($_SESSION['errors']);
// header('Location: redirect.php');
exit;
}
//This is when Javascript is turned off:
echo "<ul>";
foreach($_SESSION['errors'] as $key => $value){
echo "<li>" . $value . "</li>";
}
echo "</ul>";exit;
}else{
//Form validation successful - process data here:
echo json_encode(true);
}
}
?>
How can I make sure that the process.php is always using the latest form data?

Answer 1

I'm not sure why you store errors in the the session, but since you don't seem to clear that session, the next time you call the POST method $_SESSION['errors'] will still have the previous error in it (QFFE), hence the output.