DataTable分组归类

#region 对DataTable进行分组 + public void GroupDataRows(IEnumerable<DataRow> source, List<DataTable> destination, string[] groupByFields, int fieldIndex, DataTable schema)
        /// <summary>
        /// 对DataTable进行分组
        /// </summary>
        /// <param name="source">要分组DataTable的Row集合</param>
        /// <param name="destination">分组之后的数据</param>
        /// <param name="groupByFields">分组字段</param>
        /// <param name="fieldIndex">字段索引（从什么字段开始）</param>
        /// <param name="schema">要分组DataTable</param>
        public void GroupDataRows(IEnumerable<DataRow> source, List<DataTable> destination, string[] groupByFields, int fieldIndex, DataTable schema)
        {
            if (fieldIndex >= groupByFields.Length || fieldIndex < 0)
            {
                DataTable dt = schema.Clone();
                foreach (DataRow row in source)
                {
                    DataRow dr = dt.NewRow();
                    dr.ItemArray = row.ItemArray;
                    dt.Rows.Add(dr);
                }
                destination.Add(dt);
                return;
            }

            var results = source.GroupBy(o => o[groupByFields[fieldIndex]]);
            foreach (var rows in results)
            {
                GroupDataRows(rows, destination, groupByFields, fieldIndex + 1, schema);
            }

            fieldIndex++;
        }
        #endregion