asp.net datatable导出(转)

/// <summary>
        /// 将DataTable导出为Excel(csv)
        /// </summary>
        /// <param name="table">DataTable数据源</param>
        /// <param name="name">文件名</param>
        public static void ExportToSpreadsheet(DataTable table, string name)
        {
            Random r = new Random();
            string rf = "";
            for (int j = 0; j < 10; j++)
            {
                rf = r.Next(int.MaxValue).ToString();
            }

            HttpContext context = HttpContext.Current;
            context.Response.Clear();

            context.Response.ContentType = "text/csv";
            context.Response.ContentEncoding = System.Text.Encoding.UTF8;
            context.Response.AppendHeader("Content-Disposition", "attachment; filename=" + name + rf + ".xls");
            context.Response.BinaryWrite(System.Text.Encoding.UTF8.GetPreamble());

            foreach (DataColumn column in table.Columns)
            {
                context.Response.Write(column.ColumnName + ",");
                //context.Response.Write(column.ColumnName + "(" + column.DataType + "),");
            }

            context.Response.Write(Environment.NewLine);
            double test;

            foreach (DataRow row in table.Rows)
            {
                for (int i = 0; i < table.Columns.Count; i++)
                {
                    switch (table.Columns[i].DataType.ToString())
                    {
                        case "System.String":
                            if (double.TryParse(row[i].ToString(), out test)) context.Response.Write("=");
                            context.Response.Write("\"" + row[i].ToString().Replace("\"", "\"\"") + "\",");
                            break;
                        case "System.DateTime":
                            if (row[i].ToString() != "")
                                context.Response.Write("\"" + ((DateTime)row[i]).ToString("yyyy-MM-dd hh:mm:ss") + "\",");
                            else
                                context.Response.Write("\"" + row[i].ToString().Replace("\"", "\"\"") + "\",");
                            break;
                        default:
                            context.Response.Write("\"" + row[i].ToString().Replace("\"", "\"\"") + "\",");
                            break;
                    }
                }
                context.Response.Write(Environment.NewLine);
            }

            context.Response.End();

        }


public static void ExporttoExcel(HttpContext context, DataTable table)
        {
            context.Response.Clear();
            context.Response.Buffer = true;
            context.Response.ContentType = "application/vnd.ms-excel";
            context.Response.AppendHeader("Content-Disposition", "attachment; filename=" + DateTime.Now.Ticks + ".xlsx");
            context.Response.Write("<table border=1><tr bgcolor=#AAAAAA >");

            foreach (DataColumn item in table.Columns)
            {
                context.Response.Write("<th>" + item.ColumnName + "</th>");
            }

            context.Response.Write("</tr>");

            foreach (DataRow row in table.Rows)
            {
                string htmltable = "<tr>";
                for (int i = 0; i < table.Columns.Count; i++)
                {
                    htmltable += "<td style='vnd.ms-excel.numberformat:@'>" + row[i].ToString() + "</td>";
                }
                htmltable += "</tr>";
                context.Response.Write(htmltable);
            }
            context.Response.Write("</table>");
            context.Response.End();
        }