public async Task OnGet()
        {
            string urlString = Request.Query["feedurl"];
            Uri    feedUrl   = null;

            if (!string.IsNullOrEmpty(urlString))
            {
                try
                {
                    feedUrl   = new Uri(urlString);
                    NewsItems = await _newsItemRepository.GetNewsItems(feedUrl);
                }
                catch (UriFormatException)
                {
                    ErrorText = "There was a problem parsing the URL.";
                    return;
                }
                catch (AggregateException ae)
                {
                    ae.Handle((x) =>
                    {
                        if (x is XmlException)
                        {
                            ErrorText = "There was a problem parsing the feed. Are you sure that URL is a syndication feed?";
                            return(true);
                        }
                        return(false);
                    });
                }
            }
        }