如何添加到HttpResponseMessage文件和字符串

Question

I have a code that return file with HttpResponseMessage , I want to add the contact also string, how can I do that?

[HttpPost]
public IHttpActionResult GetPlaylistXml(int playlistId, [FromBody] JObject data)
{
    ....
    var serializer = new XmlSerializer(typeof(playList));
    using (var memStream = new MemoryStream())
    {
        serializer.Serialize(memStream, playList);

        var result = new HttpResponseMessage(HttpStatusCode.OK)
        {
            Content = new ByteArrayContent(memStream.ToArray(), 0, (int)memStream.Length)
        };
        result.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
        {
            FileName = playlist.Title + ".xml"
        };
        result.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");

        var response = ResponseMessage(result);

        return response;
    }
}

Answer 1

There are several options depending on your preference and possibly limitations based on the existing platform:

Option 1

You can leave your code as is and read the file from the stream and read the file name from the headers (I'd personally recommend this unless there is some limitation preventing you from doing this)

Option 2

Create a model and return both in json format:

[HttpPost]
public IHttpActionResult GetPlaylistXml(int playlistId, [FromBody] JObject data)
{
    ....
    var serializer = new XmlSerializer(typeof(playList));
    using (var memStream = new MemoryStream())
    {
        serializer.Serialize(memStream, playList);

        var returnModel = new 
        {
           Title = playList.Title,
           // either a byte array (which is converted to Base64, or the XML string)
           Playlist = memStream.ToArray() 
        };

        return Json(returnModel);
    }
}

Option 3

Make your endpoints more REST like and have two endpoints, one for retrieving information about the playlist and one for retrieving the playlist file:

[HttpGet]
[Route("playlist/{id}")]
public IHttpActionResult GetPlaylistMetaData(int id)
{
    return Json(new {
        Id = 1,
        Title = "My Playlist",
        TrackCount = 24,
        ...
    });
}

[HttpGet]
[Route("playlist/{id}/file")]
public IHttpActionResult GetPlaylistFile(int id)
{
    ....
    var serializer = new XmlSerializer(typeof(playList));
    using (var memStream = new MemoryStream())
    {
        serializer.Serialize(memStream, playList);

        var result = new HttpResponseMessage(HttpStatusCode.OK)
        {
            Content = new ByteArrayContent(memStream.ToArray(), 0, (int)memStream.Length)
        };
        result.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
        {
            FileName = playlist.Title + ".xml"
        };
        result.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");

        var response = ResponseMessage(result);

        return response;
    }
}

I hope this helps.