private async Task FetchNewsPages()
{
var pages = await NewsPageViewModel.FetchNewsPages(ServiceProvider, 30);
var sortedPages = pages.OrderBy(x => x.Date).Reverse().ToList();
Dispatcher.Invoke(() => NewsPages = new ObservableList <NewsPageViewModel>(sortedPages));
}
public static async Task <List <NewsPageViewModel> > FetchNewsPages(IViewModelServiceProvider serviceProvider, int maxCount)
{
var result = new List <NewsPageViewModel>();
var rss = new MemoryStream();
try
{
WebRequest request = WebRequest.Create(Urls.RssFeed);
using (var reponse = await request.GetResponseAsync())
{
using (var str = reponse.GetResponseStream())
{
str?.CopyTo(rss);
}
}
}
catch (Exception)
{
// Unable to reach the url, return an empty list.
return(result);
}
rss.Position = 0;
if (rss.Length == 0)
{
return(result);
}
try
{
int count = 0;
using (XmlReader rssReader = XmlReader.Create(rss))
{
rssReader.MoveToContent();
while (rssReader.ReadToFollowing("item") && count < maxCount)
{
rssReader.ReadToFollowing("title");
string title = rssReader.Read() ? rssReader.Value : null;
rssReader.ReadToFollowing("description");
string description = rssReader.Read() ? rssReader.Value : null;
rssReader.ReadToFollowing("pubDate");
var date = new DateTime();
bool dateValid = rssReader.Read() && DateTime.TryParseExact(rssReader.Value, "ddd, dd MMM yyyy HH:mm:ss zz00", CultureInfo.InvariantCulture, DateTimeStyles.None, out date);
rssReader.ReadToFollowing("link");
string link = rssReader.Read() ? rssReader.Value : null;
if (dateValid && title != null && link != null && description != null)
{
var page = new NewsPageViewModel(serviceProvider)
{
Title = title,
Url = link,
Description = description,
Date = date
};
result.Add(page);
++count;
}
}
}
}
catch (Exception)
{
result.Clear();
}
return(result);
}