与实体框架中的代码第一个外键冲突变化 [英] Conflicting changes with code first foreign key in Entity Framework

问题描述

使用适配器可以将接口而不是具体类型插入到dbcontext中。适配器自己工作，但是将任何一对一（父级子）关系保存到数据库中的麻烦：

异常来源

  public void SaveDomain（IDomain domain）{
 _entityRepositor = new Donors（）; 
 _entityRepositor.DomainReps.Add（new DomainRep（domain））; 
} 
  

InvalidOperationException

已检测到与Edonics.Repositor.DomainRep_TopLevelDomainRep关系角色DomainRep_TopLevelDomainRep_Target的冲突更改。

外键属性和导航属性应该处于同步状态？

  public class DomainRep：IDomain 
 {
 private readonly IDomain _adaptee; 
 
 
 public DomainRep（IDomain adaptee）
 {
 _adaptee = adaptee; 
} 
 
 [NotMapped] 
 public IDomain Adaptee 
 {
 get {return _adaptee; } 
} 
 
 public string Id 
 {
 get {return _adaptee.Id; } 
 set {_adaptee.Id = value; } 
} 
 
 public string TopLevelDomainRepId 
 {
 get {return _adaptee.Tld.Id; } 
 
 set {} 
} 
 
 [ForeignKey（TopLevelDomainRepId）] 
 public TopLevelDomainRep TopLevelDomainRep 
 {
 get {return new TopLevelDomainRep（Tld）; } 
 set {Tld = value.Adaptee; } 
} 
 
 public ITopLevelDomain Tld 
 {
 get {return _adaptee.Tld; } 
 set {_adaptee.Tld = value; } 
} 
 
 public string SecondLevelDomainRepId 
 {
 get {return _adaptee.Sld.Id; } 
 
 set {} 
} 
 
 [ForeignKey（SecondLevelDomainRepId）] 
 public SecondLevelDomainRep SecondLevelDomainRep 
 {
 get {return new SecondLevelDomainRep（Sld）; } 
 set {Sld = value.Adaptee; } 
} 
 
 public ISecondLevelDomain Sld 
 {
 get {return _adaptee.Sld; } 
 set {_adaptee.Sld = value; 
} 
 
} 
  

任何想法？

解决方案

您的适配器模式会干扰EF的工作原理。您为实体的导航属性提供了不同的实现。例如，如果您访问 TopLevelDomainRep 属性多次，它将返回多个实例，但具有相同的ID /实体密钥。 EF只处理给定主键值的每个上下文的单个实例。

您可以在EF实体之上创建一个域层，或者按预期的方式使用EF实体到。

im using an adapter to be able to plug interfaces rather than concrete types into dbcontext. the adapter works on its own, but im having trouble with getting the any one-to-one (parent child) relationships to be saved into the database:

Exception Source

public void SaveDomain(IDomain domain){
    _entityRepositor = new Donors();
    _entityRepositor.DomainReps.Add(new DomainRep(domain));                
}

InvalidOperationException

Conflicting changes to the role 'DomainRep_TopLevelDomainRep_Target' of the relationship 'Edonics.Repositor.DomainRep_TopLevelDomainRep' have been detected.

The Foreign Key Properties and the Navigation Properties Should Be in Sync?

public class DomainRep: IDomain
{
    private readonly IDomain _adaptee;        


    public DomainRep(IDomain adaptee)
    {
        _adaptee = adaptee;
    }

    [NotMapped]
    public IDomain Adaptee
    {
        get { return _adaptee; }
    }

    public string Id
    {
        get { return _adaptee.Id; }
        set { _adaptee.Id = value; }
    }

    public string TopLevelDomainRepId
    {
        get { return _adaptee.Tld.Id; }

        set { }
    }

    [ForeignKey("TopLevelDomainRepId")]
    public TopLevelDomainRep TopLevelDomainRep
    {
        get { return new TopLevelDomainRep(Tld); }
        set { Tld = value.Adaptee; }
    }

    public ITopLevelDomain Tld
    {
        get { return _adaptee.Tld; }
        set { _adaptee.Tld = value; }
    }

    public string SecondLevelDomainRepId
    {
        get { return _adaptee.Sld.Id; }  

        set { } 
    }

    [ForeignKey("SecondLevelDomainRepId")]
    public SecondLevelDomainRep SecondLevelDomainRep
    {
        get { return new SecondLevelDomainRep(Sld); }
        set { Sld = value.Adaptee; }
    }

    public ISecondLevelDomain Sld
    {
        get { return _adaptee.Sld; }
        set { _adaptee.Sld = value; }
    }

}

Any ideas?

解决方案

Your adapter pattern interfere with how EF works. You are providing a different implementation for the navigational properties of the entity. For example, if you access TopLevelDomainRep property several times it will return multiple instances but with the same ID/Entity Key. EF handles only single instance per context for a given primary key value.

Either you create a domain layer on top of EF entities or you use EF entities the way it was expected to.

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