关于DataTable的处理

 public static DataTable CreateNewTable()
        {
            DataTable dt = new DataTable();
            dt.Columns.AddRange(new DataColumn[]
            {  
                new DataColumn("tmstamp",typeof(DateTime)),  
                new DataColumn("operator",typeof(string)),  
                 new DataColumn("deviceid",typeof(int)),
                  new DataColumn("message",typeof(string)),  
                             
            });
            return dt;
        }

    this.gcProjectOrSaleExpense.DataSource = ExpensesHelper.NewProjectOrSaleExpenseDt()
    this.gvDailyExpense.AddNewRow();