RainLab\Pages\Classes\Snippet::dropDownOptionsToArray PHP Method

    protected static function dropDownOptionsToArray($optionsString)
    {
        $options = explode('|', $optionsString);
        $result = [];
        foreach ($options as $index => $optionStr) {
            $parts = explode(':', $optionStr, 2);
            if (count($parts) > 1) {
                $key = trim($parts[0]);
                if (strlen($key)) {
                    if (!preg_match('/^[0-9a-z-_]+$/i', $key)) {
                        throw new ValidationException(['snippetProperties' => Lang::get('rainlab.pages::lang.snippet.invalid_option_key', ['key' => $key])]);
                    }
                    $result[$key] = trim($parts[1]);
                } else {
                    $result[$index] = trim($optionStr);
                }
            } else {
                $result[$index] = trim($optionStr);
            }
        }
        return $result;
    }