private void RefreshVirtualDirectories() { this.SelectedVirtualDirectory = null; if (SelectedWebSite == null) { this.VirtualDirectories = new IVirtualDirectory[0]; } else { this.VirtualDirectories = SelectedWebSite.GetApps() .SelectMany(webApp => webApp.GetVirtualDirectories()) .Where(virtualDir => IsNdlVirtualDir(virtualDir)) .OrderBy(vd => vd.Name).ToArray(); if (this.VirtualDirectories.Length == 1) { this.SelectedVirtualDirectory = this.VirtualDirectories[0]; } else { this.SelectedVirtualDirectory = null; } } }