How to stream with ASP.NET Core

Question

How to properly stream response in ASP.NET Core? There is a controller like this (UPDATED CODE):

[HttpGet("test")]
public async Task GetTest()
{
    HttpContext.Response.ContentType = "text/plain";
    using (var writer = new StreamWriter(HttpContext.Response.Body))
        await writer.WriteLineAsync("Hello World");            
}

Firefox/Edge browsers show

Hello World

, while Chrome/Postman report an error:

The localhost page isn’t working

localhost unexpectedly closed the connection.

ERR_INCOMPLETE_CHUNKED_ENCODING

P.S. I am about to stream a lot of content, so I cannot specify Content-Length header in advance.

Answer 1

To stream a response that should appear to the browser like a downloaded file, you should use FileStreamResult:

[HttpGet]
public FileStreamResult GetTest()
{
  var stream = new MemoryStream(Encoding.ASCII.GetBytes("Hello World"));
  return new FileStreamResult(stream, new MediaTypeHeaderValue("text/plain"))
  {
    FileDownloadName = "test.txt"
  };
}