* @link http://jkudish.com
*/
add_action('gform_pre_render_1', 'limit_submissions_by_ip');
function limit_submissions_by_ip($form){
global $wpdb, $current_user;
$current_ip = $wpdb->escape($_SERVER['REMOTE_ADDR']);
$table_name = $wpdb->prefix.'rg_lead';
$sql = $wpdb->prepare("SELECT * FROM {$table_name} WHERE form_id = %d AND ip = %s", $form['id'], $current_ip);
$last_submission = $wpdb->get_row($sql);
if($last_submission) :
?>
Our records indicate that you've already submitted a registration from this IP address.