在我的 C# 应用程序中，我有一个插件机制，可以从配置 XML 文件中指定的不同路径加载插件 DLL。我的应用程序是可本地化的。.\en\en-US\main.resources.dll主程序集（*.exe）以标准 .NET 方式（例如；；.\de\de_DE\main.resources.dll等）在 exe 旁边具有本地化语言的附属程序集。
我开始本地化一个插件，不得不发现附属程序集必须放在 exe 旁边的文件夹中。将其放在插件 DLL 旁边时，资源管理器找不到它。
但是，由于我的插件是可互换的并且可能在不同的文件夹中，我非常希望将本地化的资源程序集放在插件旁边，而不是放在 exe 旁边。
这可能吗？！？！
我可以接受的另一种方法是将本地化资源嵌入到 DLL 中。这可能吗？？
干杯，菲利克斯
我在为我们公司开发产品时遇到了这个问题。我在任何地方都没有找到答案，所以我将在这里发布我的解决方案，以防其他人发现自己处于同样的情况。
从 .NET 4.0 开始，这个问题有了解决方案，因为附属程序集现在被传递给 AssemblyResolve 处理程序。如果您已经有一个可以从远程目录加载程序集的插件系统，那么您可能已经有一个程序集解析处理程序，您只需要扩展它以对附属资源程序集使用不同的搜索行为。如果您没有，那么实现是不平凡的，因为您基本上负责所有程序集搜索行为。我将发布一个工作解决方案的完整代码，这样无论哪种方式你都会被覆盖。首先，您需要在某处挂钩您的 AssemblyResolve 处理程序，如下所示：
AppDomain.CurrentDomain.AssemblyResolve += ResolveAssemblyReference;
然后假设您有几个变量来保存主应用程序和插件目录的路径信息，如下所示：
string _processAssemblyDirectoryPath;
List<string> _assemblySearchPaths;
然后你需要一个看起来有点像这样的小辅助方法：
static Assembly LoadAssembly(string assemblyPath)
{
// If the target assembly is already loaded, return the existing assembly instance.
Assembly[] loadedAssemblies = AppDomain.CurrentDomain.GetAssemblies();
Assembly targetAssembly = loadedAssemblies.FirstOrDefault((x) => !x.IsDynamic && String.Equals(x.Location, assemblyPath, StringComparison.OrdinalIgnoreCase));
if (targetAssembly != null)
{
return targetAssembly;
}
// Attempt to load the target assembly
return Assembly.LoadFile(assemblyPath);
}
最后，您需要所有重要的 AssemblyResolve 事件处理程序，它看起来有点像这样：
Assembly ResolveAssemblyReference(object sender, ResolveEventArgs args)
{
// Obtain information about the requested assembly
AssemblyName targetAssemblyName = new AssemblyName(args.Name);
string targetAssemblyFileName = targetAssemblyName.Name + ".dll";
// Handle satellite assembly load requests. Note that prior to .NET 4.0, satellite assemblies didn't get
// passed to AssemblyResolve handlers. When this was changed, there is a specific guarantee that if null is
// returned, normal load procedures will be followed for the satellite assembly, IE, it will be located and
// loaded in the same manner as if this event handler wasn't registered. This isn't sufficient for us
// though, as the normal load behaviour doesn't correctly locate satellite assemblies where the owning
// assembly has been loaded using Assembly.LoadFile where the assembly is located in a different folder to
// the process assembly. We handle that here by performing the satellite assembly search process ourselves.
// Also note that satellite assemblies are formally documented as requiring the file name extension of
// ".resources.dll", so detecting satellite assembly load requests by comparing with this known string is a
// valid approach.
if (targetAssemblyFileName.EndsWith(".resources.dll"))
{
// Retrieve the owning assembly which is requesting the satellite assembly
string owningAssemblyName = targetAssemblyFileName.Replace(".resources.dll", ".dll");
Assembly owningAssembly = AppDomain.CurrentDomain.GetAssemblies().FirstOrDefault((x) => x.Location.EndsWith(owningAssemblyName));
if (owningAssembly == null)
{
return null;
}
// Retrieve the directory containing the owning assembly
string owningAssemblyDirectory = Path.GetDirectoryName(owningAssembly.Location);
// Search for the required satellite assembly in resource subdirectories, and load it if found.
CultureInfo searchCulture = System.Threading.Thread.CurrentThread.CurrentCulture;
while (searchCulture != CultureInfo.InvariantCulture)
{
string resourceAssemblyPath = Path.Combine(owningAssemblyDirectory, searchCulture.Name, targetAssemblyFileName);
if (File.Exists(resourceAssemblyPath))
{
Assembly resourceAssembly = LoadAssembly(resourceAssemblyPath);
if (resourceAssembly != null)
{
return resourceAssembly;
}
}
searchCulture = searchCulture.Parent;
}
return null;
}
// If the target assembly exists in the same directory as the requesting assembly, attempt to load it now.
string requestingAssemblyPath = (args.RequestingAssembly != null) ? args.RequestingAssembly.Location : String.Empty;
if (!String.IsNullOrEmpty(requestingAssemblyPath))
{
string callingAssemblyDirectory = Path.GetDirectoryName(requestingAssemblyPath);
string targetAssemblyInCallingDirectoryPath = Path.Combine(callingAssemblyDirectory, targetAssemblyFileName);
if (File.Exists(targetAssemblyInCallingDirectoryPath))
{
try
{
return LoadAssembly(targetAssemblyInCallingDirectoryPath);
}
catch (Exception ex)
{
// Log an error
return null;
}
}
}
// If the target assembly exists in the same directory as the process executable, attempt to load it now.
string processDirectory = _processAssemblyDirectoryPath;
string targetAssemblyInProcessDirectoryPath = Path.Combine(processDirectory, targetAssemblyFileName);
if (File.Exists(targetAssemblyInProcessDirectoryPath))
{
try
{
return LoadAssembly(targetAssemblyInProcessDirectoryPath);
}
catch (Exception ex)
{
// Log an error
return null;
}
}
// Build a list of all assemblies with the requested name in the defined list of assembly search paths
Dictionary<string, AssemblyName> assemblyVersionInfo = new Dictionary<string, AssemblyName>();
foreach (string assemblyDir in _assemblySearchPaths)
{
// If the target assembly doesn't exist in this path, skip it.
string assemblyPath = Path.Combine(assemblyDir, targetAssemblyFileName);
if (!File.Exists(assemblyPath))
{
continue;
}
// Attempt to retrieve detailed information on the name and version of the target assembly
AssemblyName matchAssemblyName;
try
{
matchAssemblyName = AssemblyName.GetAssemblyName(assemblyPath);
}
catch (Exception)
{
continue;
}
// Add this assembly to the list of possible target assemblies
assemblyVersionInfo.Add(assemblyPath, matchAssemblyName);
}
// Look for an exact match of the target version
string matchAssemblyPath = assemblyVersionInfo.Where((x) => x.Value == targetAssemblyName).Select((x) => x.Key).FirstOrDefault();
if (matchAssemblyPath == null)
{
// If no exact target version match exists, look for the highest available version.
Dictionary<string, AssemblyName> assemblyVersionInfoOrdered = assemblyVersionInfo.OrderByDescending((x) => x.Value.Version).ToDictionary((x) => x.Key, (x) => x.Value);
matchAssemblyPath = assemblyVersionInfoOrdered.Select((x) => x.Key).FirstOrDefault();
}
// If no matching assembly was found, log an error, and abort any further processing.
if (matchAssemblyPath == null)
{
return null;
}
// If the target assembly is already loaded, return the existing assembly instance.
Assembly loadedAssembly = AppDomain.CurrentDomain.GetAssemblies().FirstOrDefault((x) => String.Equals(x.Location, matchAssemblyPath, StringComparison.OrdinalIgnoreCase));
if (loadedAssembly != null)
{
return loadedAssembly;
}
// Attempt to load the target assembly
try
{
return LoadAssembly(matchAssemblyPath);
}
catch (Exception ex)
{
// Log an error
}
return null;
}
该事件处理程序的第一部分处理附属资源程序集，然后是我用于常规程序集的搜索行为。这应该足以帮助任何人从头开始构建这样的系统。
好的，如果您想从标准的本地化资源绑定中“分离”您自己，并希望可以自由地从任何位置加载程序集，那么其中一个选项是
a) 实现一个接口以与该程序集中的翻译进行交互
b) 使用 Assembly.Load 函数从您想要的位置加载您想要的 .NET 程序集