Get current language in a GravityForms field

I have a multilingual WPML site. How can I add a field in my form to get the current language?

1. Add this code to your functions.php file

<?php
/**
 * Get current language in Gravity Forms
 */
add_filter('gform_field_value_lang', 'wpster_get_language');
function wpster_get_language($value) {
    if (function_exists('icl_object_id')) {
        return ICL_LANGUAGE_CODE;
    }
}
?>

2. Add an hidden field in your form

On tab “Advanced”:

• Choose “Allow field to be populated dynamically”
• Enter the field value on “Parameter Name”. For this example: lang