CsvActionResult.cs

using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Reflection;
using System.Text;
using System.Web;
using System.Web.Mvc;

namespace webnetconf.website.Helpers
{
	public class CsvActionResult<T> : FileResult
	{
		private readonly IList<T> _list;
		private readonly char _separator;

		public CsvActionResult(IList<T> list,
			string fileDownloadName, 
			char separator=',')
			: base("text/csv")
		{
			_list = list;
			FileDownloadName = fileDownloadName;
			_separator = separator;
		}

		protected override void WriteFile(HttpResponseBase response)
		{
			var outputStream = response.OutputStream;
			using (var memoryStream = new MemoryStream())
			{
				WriteList(memoryStream);
				outputStream.Write(memoryStream.GetBuffer(), 0, (int)memoryStream.Length);
			}
		}

		private void WriteList(Stream stream)
		{
			var streamWriter = new StreamWriter(stream, Encoding.Default);

			WriteHeaderLine(streamWriter);
			streamWriter.WriteLine();
			WriteDataLines(streamWriter);

			streamWriter.Flush();
		}

		private void WriteHeaderLine(StreamWriter streamWriter)
		{
			foreach (MemberInfo member in typeof(T).GetProperties())
			{
				WriteValue(streamWriter, member.Name);
			}
		}

		private void WriteDataLines(StreamWriter streamWriter)
		{
			foreach (T line in _list)
			{
				foreach (MemberInfo member in typeof(T).GetProperties())
				{
					WriteValue(streamWriter, GetPropertyValue(line, member.Name));
				}
				streamWriter.WriteLine();
			}
		}


		private void WriteValue(StreamWriter writer, String value)
		{
			writer.Write("\"");
			writer.Write(value.Replace("\"", "\"\""));
			writer.Write("\"" + _separator);
		}

		public static string GetPropertyValue(object src, string propName)
		{
            		object obj = src.GetType().GetProperty(propName).GetValue(src, null);
			return (obj != null) ? obj.ToString() : "";
		}

	}
}