DataTable行转列

   /// <summary>
        /// DataTable行转列
        /// </summary>
        /// <param name="sourcedt">源数据</param>
        /// <param name="columnList">列信息</param>
        /// <returns>转换之后的数据</returns>
        public static DataTable RevertRowToColumn(DataTable sourcedt, List<string> columnList)
        {
            DataTable dt = new DataTable();
            List<string> tableCoumn = new List<string>();
            foreach (var item in columnList)
            {
                //转换后的第一列名，以后此列每行存放sourcedt对应对应的每列列名
                dt.Columns.Add(item, typeof(string));
            }

            int l = sourcedt.Rows.Count - columnList.Count;
            if (l > 0)
            {
                //转换后的第一列名，以后此列每行存放sourcedt对应对应的每列列名
                //int l = sourcedt.Rows.Count - columnList.Count;    //dt.Columns.Add("COLUMN_NAME", typeof(string));
                for (int i = 0; i <= l; i++)
                {
                    tableCoumn.Add("VLAUE_" + (i + 1));
                }
            }

            //dt添加Columns
            for (int i = 0; i < tableCoumn.Count; i++)
            {
                dt.Columns.Add(tableCoumn[i].ToString(), typeof(string));//统一按照string类型进行存放
            }

            //对sourcedt进行转换
            for (int j = 0; j < sourcedt.Columns.Count; j++)
            {
                DataRow dr = dt.NewRow();
                string column_name = sourcedt.Columns[j].ColumnName;
                dr[0] = column_name;//把source的列名赋值给转换成行的第一列值
                for (int i = 0; i < sourcedt.Rows.Count; i++)
                {
                    string cell_value = sourcedt.Rows[i][column_name].ToString();
                    dr[i + 1] = cell_value;
                }
                dt.Rows.Add(dr);
            }
            return dt;
        }

使用：

             // 行转列
            DataTable table = Helpers.RevertRowToColumn(tableTemp, new List<string>() { "Key", "CName", "Attribute", "Value" });