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Hi there! I was trying to understand the filter_var and preg_match in-built functions…i found it little tricky so i decided to take help of the google ,but still it is away from my reach. a helping hand would be good ? thanks!!!
PHP Fatal error: Cannot redeclare testRegEx() (previously declared in /home/ccuser/workspace/php-form-val-8/src/index.php:29) in /home/ccuser/workspace/php-form-val-8/src/index.php on line 35
Here is another solution, more in line with the instructions:
Can anyone tell me why the example regex expressions in the “Custom Validations” section of the PHP course start and end with a forward slash character? This character isn’t mentioned that I can see prior to this section but then suddenly all of the shown regex expressions have it there at the start and end. E.g.
I’m stuck on step 3. Keeps telling me that “it” thinks I have a syntax error. “it” kinda sucks since the code runs fine and generates no errors. That means that "it most likely doesnt like something I typed. I’m frustrated. I tried a few other peoples solutions with the same results. Any ideas? I included all of it since I could not see anything wrong with any of it.
Thanks for any help
<?php
$feedback = "";
$success_message = "Thank you for your donation!";
$error_message = "* There was an error with your card. Please try again.";
$card_type = "";
$card_num = "";
$donation_amount = "";
if ($_SERVER["REQUEST_METHOD"] == "POST") {
$card_type = $_POST["credit"];
$card_num = $_POST["card-num"];
$donation_amount = $_POST["amount"];
// Write your code here:
if (strlen($card_num) < 100) {
if ($card_type === “mastercard”) {
if (preg_match("/5[1-5][0-9]{14}/", $card_num)) {
$feedback = $success_message;
} else {
$feedback = $error_message;
}
}
else if ($card_type === “visa”) {
if (preg_match("/4[0-9]{12}([0-9]{3})?([0-9]{3})?/", $card_num)) {
$feedback = $success_message;
} else {
$feedback = $error_message;
}
}
}
}
if (strlen($card_num) > 100) {
$feedback = $error_message;
};
?>
The preg_match pattern for Visa seems a little strange. Can anyone explain the logic?
This is the pattern: “/4[0-9]{12}([0-9]{3})?([0-9]{3})?/”
If we break it down, it first matches the number “4”, then 12 instances of the numbers 0-9, and then, apparently, an optional extra 3 instances of the numbers 0-9 and another optional extra 3 instances of the numbers 0-9.
As I see it, this would allow a Visa number with a length of 13-16 digits, as both last patterns are optional. And also, they appear to be identical, so what’s the idea?
I’ve tried replacing the pattern with a simpler version that just checks for the number 4, then 15 instances of the numbers 0-9. This works well in my testing, and is a lot simpler.
“/4[0-9]{15}/”
There might be a very good reason for checking the suggested way, but to me it doesn’t make sense.
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