EF中的可序列化类和动态代理 - 如何？

Question

在[之前的帖子]中,我被设置为必须克隆我的实体的路径.我尝试使用[codeproject]中的序列化方法.

因为这些类是由Entity Framework生成的,所以我在自定义.cs中单独标记它们,如下所示:

[Serializable]
public partial class Claims
{
}

但是,当检查时(在克隆方法中):

if (Object.ReferenceEquals(source, null))
{

被击中,我得到错误:

System.ArgumentException was unhandled by user code
  Message=The type must be serializable.
Parameter name: source
  Source=Web
  ParamName=source
  StackTrace:
       at .Web.Cloner.Clone[T](T source) in C:\Users\.\Documents\Visual Studio 2010\Projects\.\Website\Extensions.Object.cs:line 49
       at .Web.Models.Employer..ctor(User u) in C:\Users\.\Documents\Visual Studio 2010\Projects\.\Website\Models\EF.Custom.cs:line 121
       at .Web.Controllers.AuthController.Register(String Company, String GivenName, String Surname, String Title, String Department) in C:\Users\.\Documents\Visual Studio 2010\Projects\.\Website\Controllers\AuthController.cs:line 119
       at lambda_method(Closure , ControllerBase , Object[] )
       at System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters)
       at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters)
       at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
       at System.Web.Mvc.ControllerActionInvoker.<>c__DisplayClass15.<InvokeActionMethodWithFilters>b__12()
       at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation)
  InnerException: 

很明显,虽然我的课程Claims是可序列化的,但EF生成的动态代理并不是......不知何故,我的装饰品还没有流过.

这里的诀窍是什么？

*更新I*

更多上下文:我有一个类User,其中包含一个Claims定义为的属性ICollection<Claim>.在进行克隆时,传递的类型是集合,而不是Claim- 这解释了为什么克隆者抱怨该类型不可序列化.所以现在的问题是:我怎么做User.Claims序列化,因为我无法装饰属性？

Error   1   Attribute 'Serializable' is not valid on this declaration type.
It is only valid on 'class, struct, enum, delegate' declarations.   
C:\Users\.\Documents\Visual Studio 2010\Projects\.\Website\Models\EF.Custom.cs
128 10  Website

*更新II*

练习的目的是设置一个深层副本.这是它的样子:

public partial class Employer
{
    public Employer(User u)
    {
        this.Id = u.Id;
        this.GivenName = u.GivenName;
        this.Surname = u.Surname;
        this.Claims = u.Claims.Clone();
        this.Contacts = u.Contacts.Clone();
    }
}

为了u.Claims.Clone()工作,u.Claims必须是可序列化的,但不是出于上述原因.

*更新III*

好吧,我改变了方法,实现了这样的构造函数:

public partial class Employer
{
    public Employer(User u)
    {
        this.Id = u.Id;
        this.GivenName = u.GivenName;
        this.Surname = u.Surname;

        ICollection<Claim> cs = new List<Claim>();
        foreach (Claim c in u.Claims)
        {
            cs.Add(c.Clone());
        }
        this.Claims = cs;

现在它越过了clone()的检查(上面的"if"行),但现在它在:

formatter.Serialize(stream, source);

有:

System.Runtime.Serialization.SerializationException was unhandled by user code
  Message=Type 'System.Data.Entity.DynamicProxies.User_7B7AFFFE306AB2E39C07D91CC157792F503F36DFCAB490FB3333A52EA1D5DC0D' in Assembly 'EntityFrameworkDynamicProxies-Web, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' is not marked as serializable.
  Source=mscorlib
  StackTrace:
       at System.Runtime.Serialization.FormatterServices.InternalGetSerializableMembers(RuntimeType type)
       at System.Runtime.Serialization.FormatterServices.GetSerializableMembers(Type type, StreamingContext context)
       at System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.InitMemberInfo()
       at System.Runtime.Serialization.Formatters.Binary.WriteObjectInfo.InitSerialize(Object obj, ISurrogateSelector surrogateSelector, StreamingContext context, SerObjectInfoInit serObjectInfoInit, IFormatterConverter converter, ObjectWriter objectWriter, SerializationBinder binder)
       at System.Runtime.Serialization.Formatters.Binary.ObjectWriter.Write(WriteObjectInfo objectInfo, NameInfo memberNameInfo, NameInfo typeNameInfo)
       at System.Runtime.Serialization.Formatters.Binary.ObjectWriter.Serialize(Object graph, Header[] inHeaders, __BinaryWriter serWriter, Boolean fCheck)
       at System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Serialize(Stream serializationStream, Object graph, Header[] headers, Boolean fCheck)
       at System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Serialize(Stream serializationStream, Object graph)
       at Skillscore.Web.Cloner.Clone[T](T source) in C:\Users\.\Documents\Visual Studio 2010\Projects\.\Website\Extensions.Object.cs:line 62
       at Skillscore.Web.Models.Employer..ctor(User u) in C:\Users\.\Documents\Visual Studio 2010\Projects\.\Website\Models\EF.Custom.cs:line 130

感叹......一切都那么难吗？

*更新IV*

好吧,所以上面的问题是Claim该类有一个指向的导航器User- 这解释了为什么上面的方法指示了类型,.User_[...]并暗示我不仅需要使向下依赖可序列化,而且还需要备份所有路径!但是,这样做我成功克隆了对象,但我现在回到原始帖子中的问题:

System.InvalidOperationException was unhandled by user code
  Message=Conflicting changes to the role 'User' of the relationship 'EF.ClaimUser' have been detected.
  Source=System.Data.Entity
  StackTrace:
       at System.Data.Objects.DataClasses.RelatedEnd.IncludeEntity(IEntityWrapper wrappedEntity, Boolean addRelationshipAsUnchanged, Boolean doAttach)
       at System.Data.Objects.DataClasses.EntityCollection`1.Include(Boolean addRelationshipAsUnchanged, Boolean doAttach)
       at System.Data.Objects.DataClasses.RelationshipManager.AddRelatedEntitiesToObjectStateManager(Boolean doAttach)
       at System.Data.Objects.ObjectContext.AddObject(String entitySetName, Object entity)
       at System.Data.Entity.Internal.Linq.InternalSet`1.<>c__DisplayClass5.<Add>b__4()
       at System.Data.Entity.Internal.Linq.InternalSet`1.ActOnSet(Action action, EntityState newState, Object entity, String methodName)
       at System.Data.Entity.Internal.Linq.InternalSet`1.Add(Object entity)
       at System.Data.Entity.DbSet`1.Add(TEntity entity)
       at Skillscore.Web.Controllers.AuthController.Register(String Company, String GivenName, String Surname, String Title, String Department) in C:\Users\.\Documents\Visual Studio 2010\Projects\.\Website\Controllers\AuthController.cs:line 138

人.我需要一个洞.

*更新V*

我不知道问题是代理还是延迟加载,但在考虑了一点之后,似乎如果我通过序列化进行克隆,那么过去属于旧对象的东西的所有ID现在都在进行属于新的.我确实.remove()在旧物体上做了第一次,如果这有立竿见影的效果,那么跟踪中的某些内容可能并不知道.如果没有,那么在某一点会有两个具有相同ID的东西...所以我开始倾向于@ Jockey使用对象初始化程序进行克隆的想法......

Answer 1

如果要序列化实体,可以在检索该对象之前禁用代理创建.如果您想要序列化导航属性,还需要加载导航属性.

在EF 4.1中禁用代理创建

dbContext.Configuration.ProxyCreationEnabled = false;

在EF 4中

objectContext.ContextOptions.ProxyCreationEnabled = false;

例如:

var users = context.Users.Include("Claims").Where(/**/);

Answer 2

查看实体框架的 T4 模板，您可以控制 EF 如何生成实体，您必须定义它们在 T4 模板中可序列化。