C# Exportar lista para Excel

using System;
using System.Data;
using System.IO;
using System.Reflection;
using System.Text;
using System.Web;
using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
/*
 Importante
 Baixar as dll's NPOI.dll e Ionic.Zip.dll
*/

namespace Jbkr.Utils
{
    ///<summary>
    /// Classe para exportar listas para o Excel. 
    /// </summary>
    public class ExportExcel
    {
        /// <summary>
        /// Função de exportação.
        /// </summary>
        /// <param name="nomeArq">Nome que será dado ao arquivo criado.</param>
        /// <param name="lista">Lista que será convertida para excel.</param>
        /// Lista para exportação.
        public void Exportar(string nomeArq, Array lista)
        {
            // Create new Excel Workbook
            var workbook = new HSSFWorkbook();

            // Create new Excel Sheet
            var sheet = workbook.CreateSheet();

            ICellStyle dateStyle = workbook.CreateCellStyle();
            dateStyle.DataFormat = workbook.CreateDataFormat().GetFormat("dd/MM/yyyy");

            string dados = string.Empty;
            if (lista.Length < 65536)
            {
                PropertyInfo[] properties = lista.GetType().GetElementType().GetProperties();
                DataTable dt = new DataTable();

                // Create a header row
                var headerRow = sheet.CreateRow(0);

                for (int i = 0; i < properties.Length; i++)
                {
                    headerRow.CreateCell(i).SetCellValue(properties[i].Name);
                }
                int rowNumber = 1;
                for (int i = 0; i < lista.Length; i++)
                {
                    // Create a new Row
                    var row = sheet.CreateRow(rowNumber++);

                    object o = lista.GetValue(i);
                    for (int j = 0; j < properties.Length; j++)
                    {
                        // Set the Values for Cells
                        if (properties[j].PropertyType.Name == "DateTime")
                        {
                            ICell cell = row.CreateCell(j);
                            cell.SetCellValue(properties[j].GetValue(o, null) == null ? DateTime.MinValue : Convert.ToDateTime(properties[j].GetValue(o, null)));
                            cell.CellStyle = dateStyle;
                        }
                        else if (properties[j].PropertyType.Name == "Int32")
                            row.CreateCell(j).SetCellValue(properties[j].GetValue(o, null) == null ? 0 : Convert.ToInt32(properties[j].GetValue(o, null)));
                        else if ((properties[j].PropertyType.Name == "Decimal") || (properties[j].PropertyType.Name == "Double"))
                            row.CreateCell(j).SetCellValue(properties[j].GetValue(o, null) == null ? 0D : Convert.ToDouble(properties[j].GetValue(o, null)));
                        else
                            row.CreateCell(j).SetCellValue(properties[j].GetValue(o, null) == null ? string.Empty : properties[j].GetValue(o, null).ToString());
                    }
                }
                // Write the Workbook to a memory stream
                MemoryStream output = new MemoryStream();
                workbook.Write(output);

                HttpContext.Current.Response.Clear();
                HttpContext.Current.Response.Charset = "ISO-8859-1";
                HttpContext.Current.Response.ContentType = "application/vnd.ms-excel";
                HttpContext.Current.Response.AddHeader("content-disposition", "attachment;filename=" + nomeArq + ".xls");
                HttpContext.Current.Response.BinaryWrite(output.ToArray());
                HttpContext.Current.Response.End();
            }
        }
    }
}