Linq DataTable Group By 分組顯示人員明細

實現功能：

     

多個字段分組源碼樣例：

原始數據：

 

分組后的輸出結果：

源代碼：

        public static void PrintPersons()
        {
            //准備數據
            DataTable dt = new DataTable();
            dt.Columns.Add(new DataColumn("ID", typeof(int)));
            dt.Columns.Add(new DataColumn("UserName", typeof(string)));
            dt.Columns.Add(new DataColumn("DeptNo", typeof(string)));
            dt.Columns.Add(new DataColumn("DeptName", typeof(string)));
            DataRow drTemp = null;
            for (int i = 10; i <= 18; i++)
            {
                drTemp = dt.NewRow();
                drTemp["ID"] = i;
                drTemp["UserName"] = "姓名" + i.ToString();

                if (i < 15)
                {
                    drTemp["DeptNo"] = "0001";
                    drTemp["DeptName"] = "人事部";
                }
                else
                {
                    drTemp["DeptNo"] = "0002";
                    drTemp["DeptName"] = "生產部";
                }
                dt.Rows.Add(drTemp);
            }

            Console.WriteLine("分組前：");
            foreach (DataRow row in dt.Rows)
            {
                Console.WriteLine(string.Format("{0} {1} {2} {3} ", row.ItemArray));
            }
            Console.WriteLine("");

            Console.WriteLine("分組后：");

            //Linq分組查詢，並按分組顯示人員明細
            var query = from g in dt.AsEnumerable()
                        group g by new { t1 = g.Field<string>("DeptNo"), t2 = g.Field<string>("DeptName") } into companys
                        select new { DeptNo = companys.Key.t1, DeptName = companys.Key.t2, StallInfo = companys };

            foreach (var userInfo in query)
            {
                System.Collections.Generic.List<DataRow> dataRows = userInfo.StallInfo.ToList();

                Console.WriteLine(string.Format("{0}({1})人員名單: ", userInfo.DeptName, userInfo.DeptNo));
                foreach (System.Data.DataRow dr in dataRows)
                {
                    Console.WriteLine(string.Format("{0} {1} ", dr.ItemArray));
                }
            }
            Console.ReadLine();
        }