private static void AddYmlItems(this Db db, List <DbItem> items, List <DbTemplate> templates, bool merge = false)
{
if (items != null && items.Count > 0)
{
db.AddRange(LayoutItems.Get(items), merge);
db.AddRange(SystemItems.Get(items), merge);
db.AddRange(MediaItems.Get(items), merge);
db.AddRange(ContentItems.Get(items, templates), merge);
}
}