I just want to save a file temporarily and return it as a stream for a HTTP response. Azure don't like me writing things to the file system? Here's how to get around.

Returning a file in a HTTP stream , without having a physical file

var data = getData();

            var stringBuilder = new StringBuilder();
            stringBuilder.AppendLine("Header");

            foreach (var item in data)
            {
              stringBuilder.AppendLine(data.Stuff)
            }
            var response = new HttpResponseMessage(HttpStatusCode.OK);

            response.Content = new StreamContent(new MemoryStream(System.Text.Encoding.UTF8.GetBytes(stringBuilder.ToString())));
            response.Content.Headers.ContentDisposition = new System.Net.Http.Headers.ContentDispositionHeaderValue("attachment");
            response.Content.Headers.ContentDisposition.FileName = "FileName";

            return response;