与出口清单有关的问题 <T> 在MVC5中转换为CSV文件

Question

I have webapplication in MVC5.. i have to export some data to .csv file for that i searched for article and found following code on bitbucket..

 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)
        {
            try
            {
                foreach (T line in _list)
                {
                    foreach (MemberInfo member in typeof(T).GetProperties())
                    {
                        WriteValue(streamWriter, GetPropertyValue(line, member.Name));
                    }
                    streamWriter.WriteLine();
                }
            }
            catch (Exception ex)
            { }
        }


        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 value = src.GetType().GetProperty(propName).GetValue(src, null);
            return value != null ? value.ToString() : "";
        }

    }

In my Action Method i wrote following code :

    public  ActionResult ExportReportToFile(ReportCriteriaViewModels posdata, string name)
            {
  string strQuery = GetReportQuery(posdata, name);
             IEnumerable<REP_MM_DEMOGRAPHIC_CC> lstDemographics = ReportDataAccess.GetReportData<REP_MM_DEMOGRAPHIC_CC>(strQuery);
     return new CsvActionResult<REP_MM_DEMOGRAPHIC_CC>(lstDemographics.ToList(), "LISDataExport.csv");
    }

Using above code it happens nothing... browser doesn't open popup to download/Save file...

what is the problem in above code and how to solve it ??

Thanks...

Answer 1

I would not use that code. It is homemade and not ready for production usage, in my opinion.

You should definitely take advantage of WebApi (you can use them in your MVC project) and MediaType formatters to return your data in csv format.

Have a look at this tutorial, that will go through this feature.

http://www.asp.net/web-api/overview/formats-and-model-binding/media-formatters