How can you specify that a form should use HTTPS instead of HTTP upon submission in PHP?

To specify that a form should use HTTPS instead of HTTP upon submission in PHP, you can check if the request is not secure and redirect the user to the HTTPS version of the form. This ensures that sensitive information is transmitted securely over HTTPS. 

// Check if the request is not secure
if (!isset($_SERVER['HTTPS']) || $_SERVER['HTTPS'] !== 'on') {
    // Redirect to the HTTPS version of the form
    header('Location: https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI']);
    exit();
}

Keywords

PHP form submission HTTPS secure connection $_SERVER['HTTPS']

Related Questions