Code for OData 101: Building our first OData-based Windows Store app (Part 2)

Snippet1.cs

public static async Task<IEnumerable<T>> ExecuteAsync<T>(this DataServiceQuery<T> query)
{
  return await Task.Factory.FromAsync<IEnumerable<T>>(query.BeginExecute(null, null), query.EndExecute);
}

Snippet2.cs

public static IEnumerable<SampleDataItem> Search(string searchString)
{
    var regex = new Regex(searchString,
                          RegexOptions.CultureInvariant | RegexOptions.IgnoreCase |
                          RegexOptions.IgnorePatternWhitespace);
    return
        Instance.AllGroups.SelectMany(g => g.Items).Where(
            m => regex.IsMatch(m.Title) || regex.IsMatch(m.Subtitle)).Distinct(new SampleDataItemComparer());
}

Snippet3.cs

public static async void LoadMovies()
{
    IEnumerable<Title> titles =
        await
        ((DataServiceQuery<Title>)
         Context.Titles.Expand("Genres,AudioFormats,AudioFormats/Language,Awards,Cast").Where(
             t => t.Rating == "PG").OrderByDescending(t => t.ReleaseYear).Take(300)).ExecuteAsync();

    foreach (Title title in titles)
    {
        foreach (Genre netflixGenre in title.Genres)
        {
            SampleDataGroup genre = GetGroup(netflixGenre.Name);
            if (genre == null)
            {
                genre = new SampleDataGroup(netflixGenre.Name, netflixGenre.Name, String.Empty,
                                            title.BoxArt.LargeUrl,
                                            String.Empty);
                Instance.AllGroups.Add(genre);
            }
            var content = new StringBuilder();
            // Write additional things to content here if you want them to display in the item detail.
            genre.Items.Add(new SampleDataItem(title.Id, title.Name,
                                               String.Format("{0}\r\n\r\n{1} ({2})", title.Synopsis,
                                                             title.Rating,
                                                             title.ReleaseYear),
                                               title.BoxArt.HighDefinitionUrl ?? title.BoxArt.LargeUrl,
                                               "Description",
                                               content.ToString()));
        }
    }
}

Snippet4.cs

this.DefaultViewModel["QueryText"] = queryText;

Snippet5.cs

void Filter_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    // Determine what filter was selected
    var selectedFilter = e.AddedItems.FirstOrDefault() as Filter;
    if (selectedFilter != null)
    {
        // Mirror the results into the corresponding Filter object to allow the
        // RadioButton representation used when not snapped to reflect the change
        selectedFilter.Active = true;

        // TODO: Respond to the change in active filter by setting this.DefaultViewModel["Results"]
        //       to a collection of items with bindable Image, Title, Subtitle, and Description properties
        var searchValue = (string)this.DefaultViewModel["QueryText"];
        this.DefaultViewModel["Results"] = new List<SampleDataItem>(SampleDataSource.Search(searchValue));

        // Ensure results are found
        object results;
        ICollection resultsCollection;
        if (this.DefaultViewModel.TryGetValue("Results", out results) &&
            (resultsCollection = results as ICollection) != null &&
            resultsCollection.Count != 0)
        {
            VisualStateManager.GoToState(this, "ResultsFound", true);
            return;
        }
    }

    // Display informational text when there are no search results.
    VisualStateManager.GoToState(this, "NoResultsFound", true);
}