public DataTable GetAll(int pageIndex, int pageSize, string filter)
 {
     DataTable table = null;
     using (PersistentManager pm = new PersistentManager())
     {
         StockChannelDao stockChannelDao = new StockChannelDao();
         table = stockChannelDao.FindAll((pageIndex - 1) * pageSize, pageSize, filter);
     }
     return table;
 }