基于linq的group by

//这是一个将DataGridView 的数据进行统计并返回datable的方法

 public DataTable GetDtByTwo(DataGridView dgv)
        {
            DataTable dt = (DataTable)dgv.DataSource;
            DataTable dt1 = new DataTable();
            dt1.Columns.Add("ProdCode", typeof(string));
            dt1.Columns.Add("Color", typeof(string));
            dt1.Columns.Add("Quanty", typeof(decimal));
            var query = from p in dt.AsEnumerable()
                        group p by new { t1=p.Field<string>("ProdCode"),t2=p.Field<string>("Color") } into g
                        select new
                        {
                            g.Key.t1,
                            g.Key.t2,
                            TotalPrice = g.Sum(p => p.Field<decimal>("Quanty"))
                        };
            query.ToList().ForEach(p =>
            {
                object[] array = new object[3];
                array[0] = p.t1;
                array[1] = p.t2;
                array[2] = p.TotalPrice;
                dt1.Rows.Add(array);   //添加到table中
            });
            return dt1;
        }