DataTable操作

1.【将一个表中数据复制到另一个table中】：
static void Main(string[] args)
        {
            DataTable unionDataTable = new DataTable();
            DataTable dt1 = new DataTable();
           //1.为表指定列名
            unionDataTable.Columns.Add("AccountNo", typeof(string));//单号
            unionDataTable.Columns.Add("RoomNo", typeof(string));//房间号
            unionDataTable.Columns.Add("GoodsName", typeof(string));//商品名称
            unionDataTable.Columns.Add("GoodsCount", typeof(string));//商品数量
            unionDataTable.Columns.Add("State", typeof(string));//服务单状态
            unionDataTable.Columns.Add("OrderId", typeof(string));//服务订单号
             
                                                     //DataRow dr;
          //复制表结构
            dt1 = unionDataTable.Clone();


          //2.为 unionDataTable赋初值
            for (int i = 0; i <= 2; i++)
            {
                //dr = unionDataTable.NewRow();
                //dr["AccountNo"] = Guid.NewGuid().ToString();             
                unionDataTable.Rows.Add();
                unionDataTable.Rows[i][0] = "F1902150001";
                unionDataTable.Rows[i][1] = "A206";
                unionDataTable.Rows[i][2] = "送毛巾";
                unionDataTable.Rows[i][3] = "2";
                unionDataTable.Rows[i][4] = "处理中";
                unionDataTable.Rows[i][5] = "201902150001A206";       
            }
            DataTable t = unionDataTable;   
            
            dt1 = unionDataTable.Clone();
           //3.将unionDataTable表结构数据复制到dt1表
            object[] obj = new object[dt1.Columns.Count];
            for (int j = 0; j < unionDataTable.Rows.Count; j++)
            {
                unionDataTable.Rows[j].ItemArray.CopyTo(obj, 0);
                dt1.Rows.Add(obj);
            }
            //return unionDataTable;
        }

2.【将一个表中数据分组并查询特定字段】：
ZeroMoneyList：是一个datatable
  var hotelGroupData = ZeroMoneyList.AsEnumerable().GroupBy(d => d.Field<string>("HotelCode")).Select(g => new { g.Key, Data = g.Select(d => new { HotelCode = d.Field<string>("HotelCode"), AccountNo = d.Field<string>("AccountNo"), Name = d.Field<string>("Name") }) });