c# dataTable 合并两个列到一个新列中

 public static DataTable UniteDataTableColumns(DataTable dt, String newColumnName, string ColumnName1, string ColumnName2)

        {

            //汇总的表达式

            string expression = "";

            expression = String.Format("{0}+'('+{1}+')'", ColumnName1, ColumnName2);

            //增加汇总列

            System.Type myDataType = System.Type.GetType("System.String");

            DataColumn dcCol = new DataColumn(newColumnName, myDataType, expression, MappingType.Attribute);

            //增加合并列

            dt.Columns.Add(dcCol);

            return dt;

        }