Fix bug

mobile/control/member_buy.php

@@ -78,7 +78,7 @@ class member_buyControl extends mobileMemberControl {
     public function buy_step2Op() {
         $param = array();
         $param['ifcart'] = $_POST['ifcart'];
-        $cart_id = explode(',', urldecode($_POST['cart_id']));
+        $param['cart_id']  = explode(',', urldecode($_POST['cart_id']));
         Log::record('Create cart_id list'. urldecode($_POST['cart_id']),Log::ERR);
         $param['address_id'] = $_POST['address_id'];
         $param['vat_hash'] = $_POST['vat_hash'];