public class CompressFilterAttribute : ActionFilterAttribute
    {
        public override void OnActionExecuting(ActionExecutingContext filterContext)
        {
            string acceptEncoding = filterContext.HttpContext.Request.Headers["Accept-Encoding"];
            if (String.IsNullOrEmpty(acceptEncoding)) return;
            var response = filterContext.HttpContext.Response;
            acceptEncoding = acceptEncoding.ToUpperInvariant();

            if (acceptEncoding.Contains("GZIP"))
            {
                response.AppendHeader("Content-Encoding","gzip");
                response.Filter = new GZipStream(response.Filter,CompressionMode.Compress);
            }
            else if (acceptEncoding.Contains("DEFLATE"))
            {
                response.AppendHeader("Content-Encoding","deflate");
                response.Filter = new DeflateStream(response.Filter,CompressionMode.Compress);
            }
        }
    }