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PHP

Alex Watts
Alex Watts
8,396 Points
Posted by Alex Watts
Alex Watts
8,396 Points

PHP form validation with regular expression

Hello,

I am creating a website with a form, where the user can enter their details and it will send an email. Validating the form has proven to be really hard. I want to use regular expression to tell the user that they have entered an incorrect postcode and telephone/mobile number. See my code below:

$rxPostcode = "/^[A-Z]{1,2}[0-9R][0-9A-Z]?\s[0-9][ABD-HJLNP-UW-Z]{2}$/";

$rxTelephone = "/^((\(?0\d{4}\)?\s?\d{3}\s?\d{3})|(\(?0\d{3}\)?\s?\d{3}\s?\d{4})|(\(?0\d{2}\)?\s?\d{4}\s?\d{4}))(\s?\#(\d{4}|\d{3}))?$/";

$rxMobile = "/^(((\+44\s?\d{4}|\(?0\d{4}\)?)\s?\d{3}\s?\d{3})|((\+44\s?\d{3}|\(?0\d{3}\)?)\s?\d{3}\s?\d{4})|((\+44\s?\d{2}|\(?0\d{2}\)?)\s?\d{4}\s?\d{4}))(\s?\#(\d{4}|\d{3}))?$/";

if (preg_match($rxPostcode, $postcode) &&
    preg_match($rxTelephone, $telephone) ||
    preg_match($rxMobile, $telephone) &&
    empty($security)) {
 mail($to, $subject, $body);
 header("Location: /thank-you");
} else {
 echo "<h2>An error occured. Return to:</h2>";
 echo "<a href='/'>Solar Panel Funding</a>";
}

My questions are:

1) How can I test this throughly?

2) How can I display an error message in the HTML page where the form is if the regular expression pattern does not match the users details?