兑换bug修复

Gameserver/App/process/ActiveProc.php

@@ -57,7 +57,7 @@ class ActiveProc {
         if(StlUtil::dictHasProperty(ctx()->store->items, $id)){
             $itemNum = ctx()->store->items->$id;
         }
-        $cost = explode(',', $cost);
+        $cost = explode(',',$mo->cost);
         my_Assert($itemNum >= $cost[1],ErrCode::notenough_item);
         ctx()->store->removeItem($cost[0], $cost[1]);