当POCO具有IsReference = True属性时，序列化EF代理

问题描述

当使用DataContractSerializer与ProxyContractResolver时，我得到以下内容：

似乎EF代理生成器不符合IsReference属性，我在POCO上需要否则我会因为相互引用而结束堆栈溢出）。

在这种情况下，是否有任何机制来序列化EF Proxy？如何？

解决方案

我刚做了以下非常简单的例子， ProxyDataContractResolver 如预期的 - 具有循环的代理实体的图被正确序列化。

  using System; 
使用System.Collections.Generic; 
使用System.Data.Entity; 
使用System.Data.Objects; 
使用System.IO; 
使用System.Linq; 
使用System.Runtime.Serialization; 
 
命名空间CFSerialization 
 {
类程序
 {
 static void Main（string [] args）
 {
 using var context = new Context（））
 {
 context.Database.Delete（）; 
 context.Database.CreateIfNotExists（）; 
 
 context.Masters.Add（new Master 
 {
 Name =abc，
 Details = new List< Detail> 
 {
 new Detail {Name =a}，
 new Detail {Name =b}，
 new Detail {Name =c} 
} 
}）; 
 context.SaveChanges（）; 
} 
 
使用（var context = new Context（））
 {
 //这将获得代理的Master 
 var master = context.Masters。第一（）; 
 
 var serializer = new DataContractSerializer（typeof（Master），new DataContractSerializerSettings（）
 {
 DataContractResolver = new ProxyDataContractResolver（）
}）; 
 
使用（var stream = new MemoryStream（））
 {
 //这也将延迟加载所有细节
 serializer.WriteObject（stream，master）; 
 stream.Seek（0，SeekOrigin.Begin）; 
 var newMaster =（Master）serializer.ReadObject（stream）; 
} 
} 
} 
} 
 
 [DataContract（IsReference = true）] 
 public class Master 
 {
 [DataMember] 
 public int Id {get;组; } 
 [DataMember] 
 public string Name {get;组; } 
 [DataMember] 
 public virtual ICollection< Detail>细节{get;组; 
} 
 
 [DataContract（IsReference = true）] 
 public class Detail 
 {
 [DataMember] 
 public int Id {get ;组; } 
 [DataMember] 
 public string Name {get;组; } 
 [DataMember] 
 public virtual Master Master {get;组; } 
} 
 
 public class上下文：DbContext 
 {
 public DbSet< Master>大师{get;组; } 
} 
} 
  

您的模型中必须有更复杂的东西打破功能 - 所有您的实体标有 DataContract（IsReference = true）？

注意：我测试了在.NET 4.5中。

How can I serialize an Entity Framework Code First Proxy when the class it is proxying is decorated with DataContractAttribute(IsReference = true)?

When using DataContractSerializer with ProxyContractResolver, I get the following:

It seems that the EF Proxy Generator is not respecting the IsReference attribute, which I do need on the POCO (otherwise I end up with a stack overflow due to mutual referencing).

Is there any mechanism at all to serialize an EF Proxy under these circumstances? How?

解决方案

I just did following very simple example and ProxyDataContractResolver works as expected - graph of proxied entities with cycles was correctly serialized.

using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Data.Objects;
using System.IO;
using System.Linq;
using System.Runtime.Serialization;

namespace CFSerialization
{
    class Program
    {
        static void Main(string[] args)
        {
            using (var context = new Context())
            {
                context.Database.Delete();
                context.Database.CreateIfNotExists();

                context.Masters.Add(new Master
                    {
                        Name = "abc",
                        Details = new List<Detail>
                            {
                                new Detail { Name = "a" },
                                new Detail { Name = "b" },
                                new Detail { Name = "c" }
                            }
                    });
                context.SaveChanges();
            }

            using (var context = new Context())
            {
                // This will get proxied Master
                var master = context.Masters.First();

                var serializer = new DataContractSerializer(typeof(Master), new DataContractSerializerSettings()
                    {
                        DataContractResolver = new ProxyDataContractResolver()
                    });

                using (var stream = new MemoryStream())
                {
                    // This will also lazy load all details
                    serializer.WriteObject(stream, master);
                    stream.Seek(0, SeekOrigin.Begin);
                    var newMaster = (Master)serializer.ReadObject(stream);
                }
            }
        }
    }

    [DataContract(IsReference=true)]
    public class Master
    {
        [DataMember]
        public int Id { get; set; }
        [DataMember]
        public string Name { get; set; }
        [DataMember]
        public virtual ICollection<Detail> Details { get; set; }
    }

    [DataContract(IsReference=true)]
    public class Detail 
    {
        [DataMember]
        public int Id { get; set; }
        [DataMember]
        public string Name { get; set; }
        [DataMember]
        public virtual Master Master { get; set; }
    }

    public class Context : DbContext
    {
        public DbSet<Master> Masters { get; set; }
    }
}

There must be something more complicated in your model to break the functionality - are all your entities marked with DataContract(IsReference=true)?

Note: I tested it in .NET 4.5.

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