Returning an image as part of a JSON response

[Mark Swiatek]

Given a class like this:

public class UserDto

{

    public int Id { get;set; }

    public string Name { get; set; }

    public Bitmap Picture {get; set; }

}

I can make a request using the XmlServiceClient and use an ImageConverter to convert the image to a byte array that can be returned to a (partial) view as File(imgArray, "image/jpg"). I haven't been able to do the same with the JsonServiceClient. It appears to serialize differently, Does the Json serializer use a different enconding?

[Demis Bellot]

There's no support for Bitmap in the ServiceStack JSON + JSV serializers, you can either send a pull request to add it or return a byte[] in the DTO instead. 

But with any text serializer any binary data needs to be encoded (e.g. Base64) which is less efficient than returning it directly.

For this reason I don't like encoding binary payloads and will write images directly to the response stream, e.g. here's 3 different ways you can return an image from a service:

https://github.com/ServiceStack/ServiceStack/blob/master/tests/ServiceStack.WebHost.IntegrationTests/Services/HelloImage.cs

You could also download the file as an attachment if you want to add additional metadata:

new HttpResult(targetFileInfo, asAttachment:true);

https://github.com/ServiceStack/ServiceStack.Examples/blob/master/src/RestFiles/RestFiles.ServiceInterface/FilesService.cs#L30

Cheers,

--
- Demis

http://twitter.com/demisbellot

http://www.servicestack.net/mythz_blog

[Mark Swiatek]

I was coming that conclusion. Thanks for validating it.