I'm collecting form data, sending that to PHP validation script through AJAX call. The issue is on special characters the php validation script is not working as expected.
HTML:
<input type="text" name="firstName" class="firstName"
placeholder="[first name]" required autofocus maxlength="25" size="25" />
JS:
$(".button").click(function () {
var firstName = encodeURIComponent($("input.firstName").val());
var datastring = "firstName=" + firstName;
$.ajax({
type: "POST",
url: "/scripts/validateSignup.php",
data: datastring,
cache: false,
success: function (errorMessage) {
//print to screen
}
});
});
PHP Validation
$postData = $_POST;
if (Filter::validateString($postData['firstName']) == false) {
echo "Oops! Some characters used in your first name are not valid.";
}
PHP Filter
//Returns true if string is good, false otherwise
public static function validateString($string) {
$string = trim($string);
if ($string == null || $string == "") {
return false;
} else {
if (preg_match("/[^\.\,\-\_\'\"\@\?\!\:\;\$\#\%\&\+\= a-zA-Z0-9()]/", $string) == true) {
return false;
} else {
return true;
}
}
}
On an empty string it prints error to screen just fine. But if I do something like "~!@#$%^&*()", then it accepts the string as good and doesnt throw and error, even though the result of preg_match == false.