MVC Controller Using Response Stream

Question

I'm using MVC 3 I would like to dynamically create a CSV file for download, but I am unsure as to the correct MVC orientated approach.

In conventional ASP.net, I would have written something like:

Response.ClearHeaders();
Response.ContentType = "text/csv";
Response.AddHeader("content-disposition", attachment;filename='Test.csv'");
Response.Write("1,2,3");
Response.End();

I have looked at the ContentResult action but it appears that I would need to create the result as a string, i.e.

return Content(myData, "text/csv");

I could, I suppose, build a string, but since these files could be several thousand lines long, this seems inefficient to me.

Could someone point me in the right direction? Thanks.

Answer 1

I spent some time on the similar problem yesterday, and here's how to do it right way:

public ActionResult CreateReport()
{
    var reportData = MyGetDataFunction();
    var serverPipe = new AnonymousPipeServerStream(PipeDirection.Out);
    Task.Run(() => 
    {
        using (serverPipe)
        {
             MyWriteDataToFile(reportData, serverPipe)
        }
    });

    var clientPipe = new AnonymousPipeClientStream(PipeDirection.In,
             serverPipe.ClientSafePipeHandle);
    return new FileStreamResult(clientPipe, "text/csv");
}