C#高效 DataTable 行转列方法，无需修改

        #region 行转列
        /// <summary>
        /// 行转列
        /// </summary>
        /// <param name="ColumnName">固定列列名</param>
        /// <param name="dtable">数据源</param>
        /// <param name="Columns02">不固定列</param>
        ///  <param name="Quantity">数据列</param>
        /// <returns></returns>
        public static DataTable DataTableRowtoCon(string[] ColumnNames, DataTable dtable, string Columns02, string Quantity)
        {
            //从DataTable中读取不重复的行，用来构造新DataTable的列
            DataTable distinct_date = dtable.DefaultView.ToTable(true, ColumnNames);

            DataTable newDt = new DataTable();
            foreach(string ColumnName in ColumnNames)
            {
                //创建固定列
                DataColumn col01 = new DataColumn(ColumnName, Type.GetType("System.String"));
                newDt.Columns.Add(col01);
            }
            //循环创建不固定列
            for (int i = 0; i < dtable.Rows.Count; i++)
            {
                if (!newDt.Columns.Contains(dtable.Rows[i][Columns02].ToString()))
                {

                    DataColumn col02 = new DataColumn(dtable.Rows[i][Columns02].ToString(), Type.GetType("System.String"));
                    newDt.Columns.Add(col02);