上节讲到Head.cshtml,里面实际做的是根据supportRtl、supportResponsive、themeName三个变量，引入相应的CSS文件等。
接着看这一句：
@Html.Widget("head_html_tag")
扩展方法：
public static MvcHtmlString Widget(this HtmlHelper helper, string widgetZone, object additionalData = null) { return helper.Action("WidgetsByZone", "Widget", new { widgetZone = widgetZone, additionalData = additionalData }); }
其实她就是调用一个action,后面是路由信息。看一下这个action:
[ChildActionOnly] public ActionResult WidgetsByZone(string widgetZone, object additionalData = null) { var cacheKey = string.Format(ModelCacheEventConsumer.WIDGET_MODEL_KEY, _storeContext.CurrentStore.Id, widgetZone); var cacheModel = _cacheManager.Get(cacheKey, () => { //model var model = new List<RenderWidgetModel>(); var widgets = _widgetService.LoadActiveWidgetsByWidgetZone(widgetZone, _storeContext.CurrentStore.Id); foreach (var widget in widgets) { var widgetModel = new RenderWidgetModel(); string actionName; string controllerName; RouteValueDictionary routeValues; widget.GetDisplayWidgetRoute(widgetZone, out actionName, out controllerName, out routeValues); widgetModel.ActionName = actionName; widgetModel.ControllerName = controllerName; widgetModel.RouteValues = routeValues; model.Add(widgetModel); } return model; }); //no data? if (cacheModel.Count == 0) return Content(""); //"RouteValues" property of widget models depends on "additionalData". //We need to clone the cached model before modifications (the updated one should not be cached) var clonedModel = new List<RenderWidgetModel>(); foreach (var widgetModel in cacheModel) { var clonedWidgetModel = new RenderWidgetModel(); clonedWidgetModel.ActionName = widgetModel.ActionName; clonedWidgetModel.ControllerName = widgetModel.ControllerName; if (widgetModel.RouteValues != null) clonedWidgetModel.RouteValues = new RouteValueDictionary(widgetModel.RouteValues); if (additionalData != null) { if (clonedWidgetModel.RouteValues == null) clonedWidgetModel.RouteValues = new RouteValueDictionary(); clonedWidgetModel.RouteValues.Add("additionalData", additionalData); } clonedModel.Add(clonedWidgetModel); } return PartialView(clonedModel); }
看LoadActiveWidgetsByWidgetZone方法。
跟踪发现，最终通过如下方法，加载所有插件：
/// <summary> /// Load all widgets /// </summary> /// <param name="storeId">Load records allowed only in a specified store; pass 0 to load all records</param> /// <returns>Widgets</returns> public virtual IList<IWidgetPlugin> LoadAllWidgets(int storeId = 0) { return _pluginFinder.GetPlugins<IWidgetPlugin>(storeId: storeId).ToList(); }
调用的是：
/// <summary> /// Gets plugins /// </summary> /// <typeparam name="T">The type of plugins to get.</typeparam> /// <param name="loadMode">Load plugins mode</param> /// <param name="storeId">Load records allowed only in a specified store; pass 0 to load all records</param> /// <param name="group">Filter by plugin group; pass null to load all records</param> /// <returns>Plugins</returns> public virtual IEnumerable<T> GetPlugins<T>(LoadPluginsMode loadMode = LoadPluginsMode.InstalledOnly, int storeId = 0, string group = null) where T : class, IPlugin { return GetPluginDescriptors<T>(loadMode, storeId, group).Select(p => p.Instance<T>()); }
调用：
/// <summary> /// Get plugin descriptors /// </summary> /// <typeparam name="T">The type of plugin to get.</typeparam> /// <param name="loadMode">Load plugins mode</param> /// <param name="storeId">Load records allowed only in a specified store; pass 0 to load all records</param> /// <param name="group">Filter by plugin group; pass null to load all records</param> /// <returns>Plugin descriptors</returns> public virtual IEnumerable<PluginDescriptor> GetPluginDescriptors<T>(LoadPluginsMode loadMode = LoadPluginsMode.InstalledOnly, int storeId = 0, string group = null) where T : class, IPlugin { return GetPluginDescriptors(loadMode, storeId, group) .Where(p => typeof(T).IsAssignableFrom(p.PluginType)); }
我们看到它取出的是IEnumerable<PluginDescriptor> 然后筛选是IWidgetPlugin的子类吧 应该是。。。
public virtual IEnumerable<PluginDescriptor> GetPluginDescriptors(LoadPluginsMode loadMode = LoadPluginsMode.InstalledOnly, int storeId = 0, string group = null) { //ensure plugins are loaded EnsurePluginsAreLoaded(); return _plugins.Where(p => CheckLoadMode(p, loadMode) && AuthenticateStore(p, storeId) && CheckGroup(p, group)); }
先确保插件已加载，如下：
protected virtual void EnsurePluginsAreLoaded() { if (!_arePluginsLoaded) { var foundPlugins = PluginManager.ReferencedPlugins.ToList(); foundPlugins.Sort(); _plugins = foundPlugins.ToList(); _arePluginsLoaded = true; } }
看一下PluginManager:
//Contributor: Umbraco (http://www.umbraco.com). Thanks a lot! //SEE THIS POST for full details of what this does - http://shazwazza.com/post/Developing-a-plugin-framework-in-ASPNET-with-medium-trust.aspx [assembly: PreApplicationStartMethod(typeof(PluginManager), "Initialize")] namespace Nop.Core.Plugins { /// <summary> /// Sets the application up for the plugin referencing /// </summary> public class PluginManager { #region Const private const string InstalledPluginsFilePath = "~/App_Data/InstalledPlugins.txt"; private const string PluginsPath = "~/Plugins"; private const string ShadowCopyPath = "~/Plugins/bin"; #endregion #region Fields private static readonly ReaderWriterLockSlim Locker = new ReaderWriterLockSlim(); private static DirectoryInfo _shadowCopyFolder; private static bool _clearShadowDirectoryOnStartup; #endregion #region Methods /// <summary> /// Returns a collection of all referenced plugin assemblies that have been shadow copied /// </summary> public static IEnumerable<PluginDescriptor> ReferencedPlugins { get; set; } /// <summary> /// Returns a collection of all plugin which are not compatible with the current version /// </summary> public static IEnumerable<string> IncompatiblePlugins { get; set; } /// <summary> /// Initialize /// </summary> public static void Initialize() { using (new WriteLockDisposable(Locker)) { // TODO: Add verbose exception handling / raising here since this is happening on app startup and could // prevent app from starting altogether var pluginFolder = new DirectoryInfo(HostingEnvironment.MapPath(PluginsPath)); _shadowCopyFolder = new DirectoryInfo(HostingEnvironment.MapPath(ShadowCopyPath)); var referencedPlugins = new List<PluginDescriptor>(); var incompatiblePlugins = new List<string>(); _clearShadowDirectoryOnStartup = !String.IsNullOrEmpty(ConfigurationManager.AppSettings["ClearPluginsShadowDirectoryOnStartup"]) && Convert.ToBoolean(ConfigurationManager.AppSettings["ClearPluginsShadowDirectoryOnStartup"]); try { var installedPluginSystemNames = PluginFileParser.ParseInstalledPluginsFile(GetInstalledPluginsFilePath()); Debug.WriteLine("Creating shadow copy folder and querying for dlls"); //ensure folders are created Directory.CreateDirectory(pluginFolder.FullName); Directory.CreateDirectory(_shadowCopyFolder.FullName); //get list of all files in bin var binFiles = _shadowCopyFolder.GetFiles("*", SearchOption.AllDirectories); if (_clearShadowDirectoryOnStartup) { //clear out shadow copied plugins foreach (var f in binFiles) { Debug.WriteLine("Deleting " + f.Name); try { File.Delete(f.FullName); } catch (Exception exc) { Debug.WriteLine("Error deleting file " + f.Name + ". Exception: " + exc); } } } //load description files foreach (var dfd in GetDescriptionFilesAndDescriptors(pluginFolder)) { var descriptionFile = dfd.Key; var pluginDescriptor = dfd.Value; //ensure that version of plugin is valid if (!pluginDescriptor.SupportedVersions.Contains(NopVersion.CurrentVersion, StringComparer.InvariantCultureIgnoreCase)) { incompatiblePlugins.Add(pluginDescriptor.SystemName); continue; } //some validation if (String.IsNullOrWhiteSpace(pluginDescriptor.SystemName)) throw new Exception(string.Format("A plugin '{0}' has no system name. Try assigning the plugin a unique name and recompiling.", descriptionFile.FullName)); if (referencedPlugins.Contains(pluginDescriptor)) throw new Exception(string.Format("A plugin with '{0}' system name is already defined", pluginDescriptor.SystemName)); //set 'Installed' property pluginDescriptor.Installed = installedPluginSystemNames .FirstOrDefault(x => x.Equals(pluginDescriptor.SystemName, StringComparison.InvariantCultureIgnoreCase)) != null; try { if (descriptionFile.Directory == null) throw new Exception(string.Format("Directory cannot be resolved for '{0}' description file", descriptionFile.Name)); //get list of all DLLs in plugins (not in bin!) var pluginFiles = descriptionFile.Directory.GetFiles("*.dll", SearchOption.AllDirectories) //just make sure we're not registering shadow copied plugins .Where(x => !binFiles.Select(q => q.FullName).Contains(x.FullName)) .Where(x => IsPackagePluginFolder(x.Directory)) .ToList(); //other plugin description info var mainPluginFile = pluginFiles .FirstOrDefault(x => x.Name.Equals(pluginDescriptor.PluginFileName, StringComparison.InvariantCultureIgnoreCase)); pluginDescriptor.OriginalAssemblyFile = mainPluginFile; //shadow copy main plugin file pluginDescriptor.ReferencedAssembly = PerformFileDeploy(mainPluginFile); //load all other referenced assemblies now foreach (var plugin in pluginFiles .Where(x => !x.Name.Equals(mainPluginFile.Name, StringComparison.InvariantCultureIgnoreCase)) .Where(x => !IsAlreadyLoaded(x))) PerformFileDeploy(plugin); //init plugin type (only one plugin per assembly is allowed) foreach (var t in pluginDescriptor.ReferencedAssembly.GetTypes()) if (typeof(IPlugin).IsAssignableFrom(t)) if (!t.IsInterface) if (t.IsClass && !t.IsAbstract) { pluginDescriptor.PluginType = t; break; } referencedPlugins.Add(pluginDescriptor); } catch (ReflectionTypeLoadException ex) { var msg = string.Empty; foreach (var e in ex.LoaderExceptions) msg += e.Message + Environment.NewLine; var fail = new Exception(msg, ex); Debug.WriteLine(fail.Message, fail); throw fail; } } } catch (Exception ex) { var msg = string.Empty; for (var e = ex; e != null; e = e.InnerException) msg += e.Message + Environment.NewLine; var fail = new Exception(msg, ex); Debug.WriteLine(fail.Message, fail); throw fail; } ReferencedPlugins = referencedPlugins; IncompatiblePlugins = incompatiblePlugins; } } /// <summary> /// Mark plugin as installed /// </summary> /// <param name="systemName">Plugin system name</param> public static void MarkPluginAsInstalled(string systemName) { if (String.IsNullOrEmpty(systemName)) throw new ArgumentNullException("systemName"); var filePath = HostingEnvironment.MapPath(InstalledPluginsFilePath); if (!File.Exists(filePath)) using (File.Create(filePath)) { //we use 'using' to close the file after it's created } var installedPluginSystemNames = PluginFileParser.ParseInstalledPluginsFile(GetInstalledPluginsFilePath()); bool alreadyMarkedAsInstalled = installedPluginSystemNames .FirstOrDefault(x => x.Equals(systemName, StringComparison.InvariantCultureIgnoreCase)) != null; if (!alreadyMarkedAsInstalled) installedPluginSystemNames.Add(systemName); PluginFileParser.SaveInstalledPluginsFile(installedPluginSystemNames,filePath); } /// <summary> /// Mark plugin as uninstalled /// </summary> /// <param name="systemName">Plugin system name</param> public static void MarkPluginAsUninstalled(string systemName) { if (String.IsNullOrEmpty(systemName)) throw new ArgumentNullException("systemName"); var filePath = HostingEnvironment.MapPath(InstalledPluginsFilePath); if (!File.Exists(filePath)) using (File.Create(filePath)) { //we use 'using' to close the file after it's created } var installedPluginSystemNames = PluginFileParser.ParseInstalledPluginsFile(GetInstalledPluginsFilePath()); bool alreadyMarkedAsInstalled = installedPluginSystemNames .FirstOrDefault(x => x.Equals(systemName, StringComparison.InvariantCultureIgnoreCase)) != null; if (alreadyMarkedAsInstalled) installedPluginSystemNames.Remove(systemName); PluginFileParser.SaveInstalledPluginsFile(installedPluginSystemNames,filePath); } /// <summary> /// Mark plugin as uninstalled /// </summary> public static void MarkAllPluginsAsUninstalled() { var filePath = HostingEnvironment.MapPath(InstalledPluginsFilePath); if (File.Exists(filePath)) File.Delete(filePath); } #endregion #region Utilities /// <summary> /// Get description files /// </summary> /// <param name="pluginFolder">Plugin direcotry info</param> /// <returns>Original and parsed description files</returns> private static IEnumerable<KeyValuePair<FileInfo, PluginDescriptor>> GetDescriptionFilesAndDescriptors(DirectoryInfo pluginFolder) { if (pluginFolder == null) throw new ArgumentNullException("pluginFolder"); //create list (<file info, parsed plugin descritor>) var result = new List<KeyValuePair<FileInfo, PluginDescriptor>>(); //add display order and path to list foreach (var descriptionFile in pluginFolder.GetFiles("Description.txt", SearchOption.AllDirectories)) { if (!IsPackagePluginFolder(descriptionFile.Directory)) continue; //parse file var pluginDescriptor = PluginFileParser.ParsePluginDescriptionFile(descriptionFile.FullName); //populate list result.Add(new KeyValuePair<FileInfo, PluginDescriptor>(descriptionFile, pluginDescriptor)); } //sort list by display order. NOTE: Lowest DisplayOrder will be first i.e 0 , 1, 1, 1, 5, 10 //it's required: http://www.nopcommerce.com/boards/t/17455/load-plugins-based-on-their-displayorder-on-startup.aspx result.Sort((firstPair, nextPair) => firstPair.Value.DisplayOrder.CompareTo(nextPair.Value.DisplayOrder)); return result; } /// <summary> /// Indicates whether assembly file is already loaded /// </summary> /// <param name="fileInfo">File info</param> /// <returns>Result</returns> private static bool IsAlreadyLoaded(FileInfo fileInfo) { //compare full assembly name //var fileAssemblyName = AssemblyName.GetAssemblyName(fileInfo.FullName); //foreach (var a in AppDomain.CurrentDomain.GetAssemblies()) //{ // if (a.FullName.Equals(fileAssemblyName.FullName, StringComparison.InvariantCultureIgnoreCase)) // return true; //} //return false; //do not compare the full assembly name, just filename try { string fileNameWithoutExt = Path.GetFileNameWithoutExtension(fileInfo.FullName); if (fileNameWithoutExt == null) throw new Exception(string.Format("Cannot get file extnension for {0}", fileInfo.Name)); foreach (var a in AppDomain.CurrentDomain.GetAssemblies()) { string assemblyName = a.FullName.Split(new[] { ',' }).FirstOrDefault(); if (fileNameWithoutExt.Equals(assemblyName, StringComparison.InvariantCultureIgnoreCase)) return true; } } catch (Exception exc) { Debug.WriteLine("Cannot validate whether an assembly is already loaded. " + exc); } return false; } /// <summary> /// Perform file deply /// </summary> /// <param name="plug">Plugin file info</param> /// <returns>Assembly</returns> private static Assembly PerformFileDeploy(FileInfo plug) { if (plug.Directory.Parent == null) throw new InvalidOperationException("The plugin directory for the " + plug.Name + " file exists in a folder outside of the allowed nopCommerce folder heirarchy"); FileInfo shadowCopiedPlug; if (CommonHelper.GetTrustLevel() != AspNetHostingPermissionLevel.Unrestricted) { //all plugins will need to be copied to ~/Plugins/bin/ //this is aboslutely required because all of this relies on probingPaths being set statically in the web.config //were running in med trust, so copy to custom bin folder var shadowCopyPlugFolder = Directory.CreateDirectory(_shadowCopyFolder.FullName); shadowCopiedPlug = InitializeMediumTrust(plug, shadowCopyPlugFolder); } else { var directory = AppDomain.CurrentDomain.DynamicDirectory; Debug.WriteLine(plug.FullName + " to " + directory); //were running in full trust so copy to standard dynamic folder shadowCopiedPlug = InitializeFullTrust(plug, new DirectoryInfo(directory)); } //we can now register the plugin definition var shadowCopiedAssembly = Assembly.Load(AssemblyName.GetAssemblyName(shadowCopiedPlug.FullName)); //add the reference to the build manager Debug.WriteLine("Adding to BuildManager: '{0}'", shadowCopiedAssembly.FullName); BuildManager.AddReferencedAssembly(shadowCopiedAssembly); return shadowCopiedAssembly; } /// <summary> /// Used to initialize plugins when running in Full Trust /// </summary> /// <param name="plug"></param> /// <param name="shadowCopyPlugFolder"></param> /// <returns></returns> private static FileInfo InitializeFullTrust(FileInfo plug, DirectoryInfo shadowCopyPlugFolder) { var shadowCopiedPlug = new FileInfo(Path.Combine(shadowCopyPlugFolder.FullName, plug.Name)); try { File.Copy(plug.FullName, shadowCopiedPlug.FullName, true); } catch (IOException) { Debug.WriteLine(shadowCopiedPlug.FullName + " is locked, attempting to rename"); //this occurs when the files are locked, //for some reason devenv locks plugin files some times and for another crazy reason you are allowed to rename them //which releases the lock, so that it what we are doing here, once it's renamed, we can re-shadow copy try { var oldFile = shadowCopiedPlug.FullName + Guid.NewGuid().ToString("N") + ".old"; File.Move(shadowCopiedPlug.FullName, oldFile); } catch (IOException exc) { throw new IOException(shadowCopiedPlug.FullName + " rename failed, cannot initialize plugin", exc); } //ok, we've made it this far, now retry the shadow copy File.Copy(plug.FullName, shadowCopiedPlug.FullName, true); } return shadowCopiedPlug; } /// <summary> /// Used to initialize plugins when running in Medium Trust /// </summary> /// <param name="plug"></param> /// <param name="shadowCopyPlugFolder"></param> /// <returns></returns> private static FileInfo InitializeMediumTrust(FileInfo plug, DirectoryInfo shadowCopyPlugFolder) { var shouldCopy = true; var shadowCopiedPlug = new FileInfo(Path.Combine(shadowCopyPlugFolder.FullName, plug.Name)); //check if a shadow copied file already exists and if it does, check if it's updated, if not don't copy if (shadowCopiedPlug.Exists) { //it's better to use LastWriteTimeUTC, but not all file systems have this property //maybe it is better to compare file hash? var areFilesIdentical = shadowCopiedPlug.CreationTimeUtc.Ticks >= plug.CreationTimeUtc.Ticks; if (areFilesIdentical) { Debug.WriteLine("Not copying; files appear identical: '{0}'", shadowCopiedPlug.Name); shouldCopy = false; } else { //delete an existing file //More info: http://www.nopcommerce.com/boards/t/11511/access-error-nopplugindiscountrulesbillingcountrydll.aspx?p=4#60838 Debug.WriteLine("New plugin found; Deleting the old file: '{0}'", shadowCopiedPlug.Name); File.Delete(shadowCopiedPlug.FullName); } } if (shouldCopy) { try { File.Copy(plug.FullName, shadowCopiedPlug.FullName, true); } catch (IOException) { Debug.WriteLine(shadowCopiedPlug.FullName + " is locked, attempting to rename"); //this occurs when the files are locked, //for some reason devenv locks plugin files some times and for another crazy reason you are allowed to rename them //which releases the lock, so that it what we are doing here, once it's renamed, we can re-shadow copy try { var oldFile = shadowCopiedPlug.FullName + Guid.NewGuid().ToString("N") + ".old"; File.Move(shadowCopiedPlug.FullName, oldFile); } catch (IOException exc) { throw new IOException(shadowCopiedPlug.FullName + " rename failed, cannot initialize plugin", exc); } //ok, we've made it this far, now retry the shadow copy File.Copy(plug.FullName, shadowCopiedPlug.FullName, true); } } return shadowCopiedPlug; } /// <summary> /// Determines if the folder is a bin plugin folder for a package /// </summary> /// <param name="folder"></param> /// <returns></returns> private static bool IsPackagePluginFolder(DirectoryInfo folder) { if (folder == null) return false; if (folder.Parent == null) return false; if (!folder.Parent.Name.Equals("Plugins", StringComparison.InvariantCultureIgnoreCase)) return false; return true; } /// <summary> /// Gets the full path of InstalledPlugins.txt file /// </summary> /// <returns></returns> private static string GetInstalledPluginsFilePath() { var filePath = HostingEnvironment.MapPath(InstalledPluginsFilePath); return filePath; } #endregion } }
从注释可以看到 他是参考了Umbraco。
调用了
/// <summary> /// Returns a collection of all referenced plugin assemblies that have been shadow copied /// </summary> public static IEnumerable<PluginDescriptor> ReferencedPlugins { get; set; }
Initialize方法应该对他进行了设置，看它都做了什么：
public static void Initialize() { using (new WriteLockDisposable(Locker)) { // TODO: Add verbose exception handling / raising here since this is happening on app startup and could // prevent app from starting altogether var pluginFolder = new DirectoryInfo(HostingEnvironment.MapPath(PluginsPath)); _shadowCopyFolder = new DirectoryInfo(HostingEnvironment.MapPath(ShadowCopyPath)); var referencedPlugins = new List<PluginDescriptor>(); var incompatiblePlugins = new List<string>(); _clearShadowDirectoryOnStartup = !String.IsNullOrEmpty(ConfigurationManager.AppSettings["ClearPluginsShadowDirectoryOnStartup"]) && Convert.ToBoolean(ConfigurationManager.AppSettings["ClearPluginsShadowDirectoryOnStartup"]); try { var installedPluginSystemNames = PluginFileParser.ParseInstalledPluginsFile(GetInstalledPluginsFilePath()); Debug.WriteLine("Creating shadow copy folder and querying for dlls"); //ensure folders are created Directory.CreateDirectory(pluginFolder.FullName); Directory.CreateDirectory(_shadowCopyFolder.FullName); //get list of all files in bin var binFiles = _shadowCopyFolder.GetFiles("*", SearchOption.AllDirectories); if (_clearShadowDirectoryOnStartup) { //clear out shadow copied plugins foreach (var f in binFiles) { Debug.WriteLine("Deleting " + f.Name); try { File.Delete(f.FullName); } catch (Exception exc) { Debug.WriteLine("Error deleting file " + f.Name + ". Exception: " + exc); } } } //load description files foreach (var dfd in GetDescriptionFilesAndDescriptors(pluginFolder)) { var descriptionFile = dfd.Key; var pluginDescriptor = dfd.Value; //ensure that version of plugin is valid if (!pluginDescriptor.SupportedVersions.Contains(NopVersion.CurrentVersion, StringComparer.InvariantCultureIgnoreCase)) { incompatiblePlugins.Add(pluginDescriptor.SystemName); continue; } //some validation if (String.IsNullOrWhiteSpace(pluginDescriptor.SystemName)) throw new Exception(string.Format("A plugin '{0}' has no system name. Try assigning the plugin a unique name and recompiling.", descriptionFile.FullName)); if (referencedPlugins.Contains(pluginDescriptor)) throw new Exception(string.Format("A plugin with '{0}' system name is already defined", pluginDescriptor.SystemName)); //set 'Installed' property pluginDescriptor.Installed = installedPluginSystemNames .FirstOrDefault(x => x.Equals(pluginDescriptor.SystemName, StringComparison.InvariantCultureIgnoreCase)) != null; try { if (descriptionFile.Directory == null) throw new Exception(string.Format("Directory cannot be resolved for '{0}' description file", descriptionFile.Name)); //get list of all DLLs in plugins (not in bin!) var pluginFiles = descriptionFile.Directory.GetFiles("*.dll", SearchOption.AllDirectories) //just make sure we're not registering shadow copied plugins .Where(x => !binFiles.Select(q => q.FullName).Contains(x.FullName)) .Where(x => IsPackagePluginFolder(x.Directory)) .ToList(); //other plugin description info var mainPluginFile = pluginFiles .FirstOrDefault(x => x.Name.Equals(pluginDescriptor.PluginFileName, StringComparison.InvariantCultureIgnoreCase)); pluginDescriptor.OriginalAssemblyFile = mainPluginFile; //shadow copy main plugin file pluginDescriptor.ReferencedAssembly = PerformFileDeploy(mainPluginFile); //load all other referenced assemblies now foreach (var plugin in pluginFiles .Where(x => !x.Name.Equals(mainPluginFile.Name, StringComparison.InvariantCultureIgnoreCase)) .Where(x => !IsAlreadyLoaded(x))) PerformFileDeploy(plugin); //init plugin type (only one plugin per assembly is allowed) foreach (var t in pluginDescriptor.ReferencedAssembly.GetTypes()) if (typeof(IPlugin).IsAssignableFrom(t)) if (!t.IsInterface) if (t.IsClass && !t.IsAbstract) { pluginDescriptor.PluginType = t; break; } referencedPlugins.Add(pluginDescriptor); } catch (ReflectionTypeLoadException ex) { var msg = string.Empty; foreach (var e in ex.LoaderExceptions) msg += e.Message + Environment.NewLine; var fail = new Exception(msg, ex); Debug.WriteLine(fail.Message, fail); throw fail; } } } catch (Exception ex) { var msg = string.Empty; for (var e = ex; e != null; e = e.InnerException) msg += e.Message + Environment.NewLine; var fail = new Exception(msg, ex); Debug.WriteLine(fail.Message, fail); throw fail; } ReferencedPlugins = referencedPlugins; IncompatiblePlugins = incompatiblePlugins; } }
try catch内部 根据 private const string InstalledPluginsFilePath = "~/App_Data/InstalledPlugins.txt"; 获得已安装插件名字的LIST<STRING>.
获得启动时清除目录为false。
调用GetDescriptionFilesAndDescriptors方法。：
/// <summary> /// Get description files /// </summary> /// <param name="pluginFolder">Plugin direcotry info</param> /// <returns>Original and parsed description files</returns> private static IEnumerable<KeyValuePair<FileInfo, PluginDescriptor>> GetDescriptionFilesAndDescriptors(DirectoryInfo pluginFolder) { if (pluginFolder == null) throw new ArgumentNullException("pluginFolder"); //create list (<file info, parsed plugin descritor>) var result = new List<KeyValuePair<FileInfo, PluginDescriptor>>(); //add display order and path to list foreach (var descriptionFile in pluginFolder.GetFiles("Description.txt", SearchOption.AllDirectories)) { if (!IsPackagePluginFolder(descriptionFile.Directory)) continue; //parse file var pluginDescriptor = PluginFileParser.ParsePluginDescriptionFile(descriptionFile.FullName); //populate list result.Add(new KeyValuePair<FileInfo, PluginDescriptor>(descriptionFile, pluginDescriptor)); } //sort list by display order. NOTE: Lowest DisplayOrder will be first i.e 0 , 1, 1, 1, 5, 10 //it's required: http://www.nopcommerce.com/boards/t/17455/load-plugins-based-on-their-displayorder-on-startup.aspx result.Sort((firstPair, nextPair) => firstPair.Value.DisplayOrder.CompareTo(nextPair.Value.DisplayOrder)); return result; }
创建一个键值对单元类的List集合。
获取pluginFolder下的所有Description .txt文件,遍历。。:
/// <summary> /// Determines if the folder is a bin plugin folder for a package /// </summary> /// <param name="folder"></param> /// <returns></returns> private static bool IsPackagePluginFolder(DirectoryInfo folder) { if (folder == null) return false; if (folder.Parent == null) return false; if (!folder.Parent.Name.Equals("Plugins", StringComparison.InvariantCultureIgnoreCase)) return false; return true; }
就是确保 这个文件夹是plugin的直接子文件夹。
然后获得插件描述文件：
public static PluginDescriptor ParsePluginDescriptionFile(string filePath) { var descriptor = new PluginDescriptor(); var text = File.ReadAllText(filePath); if (String.IsNullOrEmpty(text)) return descriptor; var settings = new List<string>(); using (var reader = new StringReader(text)) { string str; while ((str = reader.ReadLine()) != null) { if (String.IsNullOrWhiteSpace(str)) continue; settings.Add(str.Trim()); } } //Old way of file reading. This leads to unexpected behavior when a user's FTP program transfers these files as ASCII ( becomes ). //var settings = text.Split(new[] { Environment.NewLine }, StringSplitOptions.RemoveEmptyEntries); foreach (var setting in settings) { var separatorIndex = setting.IndexOf(':'); if (separatorIndex == -1) { continue; } string key = setting.Substring(0, separatorIndex).Trim(); string value = setting.Substring(separatorIndex + 1).Trim(); switch (key) { case "Group": descriptor.Group = value; break; case "FriendlyName": descriptor.FriendlyName = value; break; case "SystemName": descriptor.SystemName = value; break; case "Version": descriptor.Version = value; break; case "SupportedVersions": { //parse supported versions descriptor.SupportedVersions = value.Split(new [] { ',' }, StringSplitOptions.RemoveEmptyEntries) .Select(x => x.Trim()) .ToList(); } break; case "Author": descriptor.Author = value; break; case "DisplayOrder": { int displayOrder; int.TryParse(value, out displayOrder); descriptor.DisplayOrder = displayOrder; } break; case "FileName": descriptor.PluginFileName = value; break; case "LimitedToStores": { //parse list of store IDs foreach (var str1 in value.Split(new [] {','}, StringSplitOptions.RemoveEmptyEntries) .Select(x => x.Trim())) { int storeId; if (int.TryParse(str1, out storeId)) { descriptor.LimitedToStores.Add(storeId); } } } break; default: break; } } //nopCommerce 2.00 didn't have 'SupportedVersions' parameter //so let's set it to "2.00" if (descriptor.SupportedVersions.Count == 0) descriptor.SupportedVersions.Add("2.00"); return descriptor; }
最后根据DisplayOrder排序 返回List.
循环List根据值 ，如果不包含当前版本号，则加入到不兼容列表，并continue.
然后验证 要有systemName,并插件没哟重复。
然后根据安装文件LIST<STRING>列表查找是否已安装。
获取所有的plugin目录的DLL文件列表，并且不再BIN目录中，而且是直接子目录。
根据上步的列表找出与pluginDescriptor.PluginFileName同名的DLL文件。
然后赋值：
pluginDescriptor.OriginalAssemblyFile = mainPluginFile; //shadow copy main plugin file pluginDescriptor.ReferencedAssembly = PerformFileDeploy(mainPluginFile);