private function getStoredCsrfToken(string $formName): ?string
    {
        $csrfData = Session::getInstance()->read('__CSRF_TOKEN');
        if (is_null($csrfData)) {
            return null;
        }
        return isset($csrfData[$formName]) ? $csrfData[$formName] : null;
    }
private function getStoredCsrfToken(string $formName): ?string
    {
        $csrfData = Session::getInstance()->read('__CSRF_TOKEN');
        if (is_null($csrfData)) {
            return null;
        }
        return isset($csrfData[$formName]) ? $csrfData[$formName] : null;
    }
private function getStoredCsrfToken ( string $ formName ) : ? string { $ csrfData = Session :: getInstance ( ) -> read ( '__CSRF_TOKEN' ) ; if ( is_null ( $ csrfData ) ) { return null ; } return isset ( $ csrfData [ $ formName ] ) ? $ csrfData [ $ formName ] : null ; }
Obtains the CSRF token stored by the server for the corresponding
client. Returns null if undefined.

@param string $formName
@return null|string
Obtains the CSRF token stored by the server for the corresponding client . Returns null if undefined .