How to download file from HTTPResponseMessage

asp.net-mvc

Solution

You should use one of the Controller.File overload. The File() helper method provides support for returning the contents of a file. The MediaTypeNames class can be used to get the MIME type for a specific file name extension.

For example:

    public FileResult Download(string fileNameWithPath)
    {
        // Option 1 - Native support for file read
        return File(fileNameWithPath, System.Net.Mime.MediaTypeNames.Application.Octet, Path.GetFileName(fileNameWithPath));

        // Option 2 - Read byte array and pass to file object
        //byte[] fileBytes = System.IO.File.ReadAllBytes(fileName); return
        //File(fileBytes, System.Net.Mime.MediaTypeNames.Application.Octet,
        //fileName);
    }

Problem

I have included a link on my website to download images. When I click on the link I would like the download to automatically start. Currently when I click on the link I’m getting back the response message: Example: StatusCode: 200, ReasonPhrase: 'OK', Version: 1.1, Content: System.Net.Http.PushStreamContent, Headers: { Content-Type: application/octet-stream Content-Disposition: attachment; filename=895621d7-57a4-47a5-8dc5-ae36a2623826Banneraaaaaaaa.jpg } How do I modify the code below to start the download automatically. I think I might be returning the wrong type: Here is my code: ``` public HttpResponseMessage DownloadImageFile(string filepath) { filepath = "https://mysite.com/" + filepath; try { var response = new HttpResponseMessage(); response.Content = new PushStreamContent((Stream outputStream, HttpContent content, TransportContext context) => { try { DownloadFile(filepath, outputStream); } finally { outputStream.Close(); } }); response.Content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/octet-stream"); response.Content.Headers.ContentDisposition = new System.Net.Http.Headers.ContentDispositionHeaderValue("attachment"); response.Content.Headers.ContentDisposition.FileName = Path.GetFileName(filepath); return response; } catch (Exception ex) { } return null; } public void DownloadFile(string file, Stream response) { var bufferSize = 1024 * 1024; using (var stream = new FileStream(file, FileMode.Open, FileAccess.Read)) { var buffer = new byte[bufferSize]; var bytesRead = 0; while ((bytesRead = stream.Read(buffer, 0, bufferSize)) > 0) { response.Write(buffer, 0, bytesRead); } response.Flush(); } } } ```

Original source