asp.net DataTable 修改列值

     /// <summary>
     /// 修改数据表DataTable某一列的类型和记录值(正确步骤：1.克隆表结构，2.修改列类型，3.修改记录值，4.返回结果)
     /// </summary>
     /// <param name="orgDataTable">数据表DataTable</param>
     /// <returns>数据表DataTable</returns>
     private DataTable UpdateDataTable(DataTable orgDataTable)
     {
         DataTable dt = new DataTable();
         //克隆表结构
         dt = orgDataTable.Clone();
         foreach (DataColumn col in dt.Columns)//循环列
         {
             if (col.ColumnName == "Name")
             {
                 //修改列类型
                 col.DataType = typeof(String);
             }
         }
         foreach (DataRow dr in orgDataTable.Rows)//循环行
         {
             DataRow newdr = dt.NewRow();
             newdr["Account"] = dr["Account"];
             newdr["Name"] = dr["Name"];
             //修改记录值
             newdr["Name"] = ""+dr["Name"];
             dt.Rows.Add(newdr);
         }
         //返回结果
         return dt;
     }