/**
* Set a regex validator for a field. The validator will check if regex is matched on form correct.
*
* @param Field $field The field
* @param string $pattern The pattern to match. This function does not validate given pattern
* @param string|null $help_text Optionally set placeholder text for field i.e. DD-MM-YYYY
*/
public static function validateRegularExpression(\FormHandler\Field\Field $field, $pattern, $help_text = null)
{
$field->setExtra(' pattern="' . $pattern . '"', true)->setValidator(function ($value) use($pattern) {
return is_string($value) && preg_match($pattern, $value);
});
if (!is_null($help_text)) {
$field->setExtra(' placeholder="' . $help_text . '"', true);
}
}
