Add merged directories from the codebehind

WpfDictionaries.cs

  //Sample Usage for mahapps:
    //WpfDictionaries.AddDirectories("MahApps.Metro", "component/Styles", new string[] { "Controls", "Fonts", "Colors", "Accents/Blue", "Accents/BaseLight" }, "xaml");

    internal class WpfDictionaries
    {
        public static void AddDirectories(string domain, string prefix, IEnumerable<string> fileNames, string suffix)
        {
            fileNames.ForEach(x =>
            {
                Application.Current.Resources.MergedDictionaries.Add(new ResourceDictionary
                {
                    Source = new Uri($"pack://application:,,,/{domain};{prefix}/{x}.{suffix}", UriKind.RelativeOrAbsolute)
                });
            });
        }
    }
internal static class Extensions{
  public static void ForEach<T>(this IEnumerable<T> input, Action<T> toRunAct)
        {
            foreach (var put in input)
            {
                toRunAct(put);
            }
        }
}