Opening a NuGet package...

OpeningNugetPackage.cs

    /// From NuGetPackageExplorer's MainWindow OpenLocalPackageCore(string packagePath)
    ///
        private bool OpenLocalPackageCore(string packagePath)
        {
            IPackage package = null;

            try
            {
                string extension = Path.GetExtension(packagePath);
                if (extension.Equals(Constants.PackageExtension, StringComparison.OrdinalIgnoreCase))
                {
                    package = new ZipPackage(packagePath);
                }
                else if (extension.Equals(Constants.ManifestExtension, StringComparison.OrdinalIgnoreCase))
                {
                    var builder = new PackageBuilder(packagePath);
                    package = builder.Build();
                }
            }
            catch (Exception ex)
            {
                UIServices.Show(ex.Message, MessageLevel.Error);
                return false;
            }

            if (package != null)
            {
                // LocalPackage is below...
                LoadPackage(package, packagePath, PackageType.LocalPackage);
                return true;
            }

            return false;
        }
        
        ///
        /// This is from the same class, but it's doing ViewModel stuff we don't have to worry about...
        ///
        private void LoadPackage(IPackage package, string packagePath, PackageType packageType)
        {
            DisposeViewModel();

            if (package != null)
            {
                if (!HasLoadedContent<PackageViewer>())
                {
                    var packageViewer = new PackageViewer(UIServices, PackageChooser);
                    var binding = new Binding
                                  {
                                      Converter = new NullToVisibilityConverter(),
                                      FallbackValue = Visibility.Collapsed
                                  };
                    packageViewer.SetBinding(VisibilityProperty, binding);

                    MainContentContainer.Children.Add(packageViewer);

                    // HACK HACK: set the Export of IPackageMetadataEditor here
                    EditorService = packageViewer.PackageMetadataEditor;
                }

                PackageViewModel packageViewModel = PackageViewModelFactory.CreateViewModel(package, packagePath);
                packageViewModel.PropertyChanged += OnPackageViewModelPropertyChanged;

                DataContext = packageViewModel;
                if (!String.IsNullOrEmpty(packagePath))
                {
                    _mruManager.NotifyFileAdded(package, packagePath, packageType);
                }
            }
        }