c# - CLR 函数中的反序列化失败

Question

我用C#编写了一些文本的音标转换例程。这些例程需要一堆 aof 定义的转换规则(搜索字符串/替换字符串)。这个想法是将这些规则存储为程序集中的嵌入式资源，然后从中读取规则。反序列化的起点如下

public static phonet42n.Core.Rules Deserialize(phonet42n.Core.Rules.Ressources ressource)
{
    string ressourceName;
    phonet42n.Core.Rules returnValue;
    System.Xml.XmlReader reader;
    System.Xml.Serialization.XmlSerializer xmlSerializer;
    phonet42n.Core.SerializableRules serializeableRules;

    returnValue = new phonet42n.Core.Rules();

    switch (ressource)
    {
        case Ressources.German_01:
            ressourceName = RESSOURCE_XML_GERMAN_01;
            break;
        case Ressources.German_02:
            ressourceName = RESSOURCE_XML_GERMAN_02;
            break;
        default:
            ressourceName = RESSOURCE_XML_GERMAN_01;
            break;
    }

    using (Stream stream = Assembly.GetExecutingAssembly().GetManifestResourceStream(ressourceName))
    {
        using (reader = System.Xml.XmlReader.Create(stream))
        {
            xmlSerializer = new System.Xml.Serialization.XmlSerializer(typeof(phonet42n.Core.SerializableRules));
            serializeableRules = (phonet42n.Core.SerializableRules)xmlSerializer.Deserialize(reader);
        }
    }

    foreach (phonet42n.Core.Rule entry in serializeableRules.Rules)
    {
        if (entry.SearchString != null && entry.SearchString.Length > 0)
        {
            returnValue.Add(entry.Index, entry);
        }
    }
    return returnValue;
}

当在常规可执行文件中执行时，该应用程序工作正常。

在 SQL Server 中执行注册函数时出现以下错误:

SELECT [dbo].[Phonet42n]('mayer', 1)

产生...

Meldung 6522, Ebene 16, Status 1, Zeile 22
.NET Framework-Fehler beim Ausführen der benutzerdefinierten Routine oder des benutzerdefinierten Aggregats 'Phonet42n':
System.InvalidOperationException: Fehler im XML-Dokument (3,4). ---> System.MethodAccessException: Fehler beim Versuch der Methode "Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReader1.Read8_SerializableRules(Boolean, Boolean)", auf Methode "phonet42n.Core.Rule..ctor()" zuzugreifen.
System.MethodAccessException:
bei System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck)
bei System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark)
bei System.Activator.CreateInstance(Type type, Boolean nonPublic)
bei System.RuntimeType.CreateInstanceImpl(BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes, StackCrawlMark& stackMark)
bei System.Activator.CreateInstance(Type type, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes)
bei System.Activator.CreateInstance(Type type, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture)
bei Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReader1.Read8_SerializableRules(Boolean isNullable, Boolean checkType)
bei Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReader1.Read19_Rules()
System.InvalidOperationException:
bei System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle, XmlDeserializationEvents events)
bei System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader)
bei phonet42n.Core.Rules.Deserialize(Ressources ressource)
bei phonet42n.Core.Rules..ctor(Ressources ressource, Characters characters)
bei phonet42n.Core.HashTable..ctor(Ressources ressource)
bei phonet42n.Core.Match..ctor(Re...

有什么想法吗？

Answer 1

每当出现安全异常时，您可以首先尝试将程序集设置为 PERMISSION_SET = EXTERNAL_ACCESS，如果这不起作用，您可以尝试 UNSAFE。但是，如果有人试图动态加载程序集，那么即使对于标记为 UNSAFE 的程序集，也应禁止这样做。

由于这里的问题是想要包含一套规则，这可能会在另一个大会上完成。然后主程序集可以引用包含规则的程序集，而您只需先将包含规则的程序集加载到 SQL Server 中即可。这将允许两个程序集保持标记为 SAFE。

当然，如果没有迫切需要将规则分开，那么您也可以将它们直接放在类中的集合中。