c# - 多重性与参照约束冲突

Question

我收到以下 EF 错误:

Agent_MailingAddress: : Multiplicity conflicts with the referential constraint in Role 'Agent_MailingAddress_Target' in relationship 'Agent_MailingAddress'. Because all of the properties in the Dependent Role are non-nullable, multiplicity of the Principal Role must be 1

它似乎在它执行时抛出这个 base.OnModelCreating(modelBuilder).

这是我的模型。 FWIW，Agent继承自 User类。

public class Agent
{
    public int AgentId { get; set; }
    public int PrimaryAddressId { get; set; }
    public Address PrimaryAddress { get; set; }
    public int? MailingAddressId { get; set; }
    public Address MailingAddress { get; set; }
}

public class Address
{
    public int AddressId { get; set; }
    public string AddressLine1 { get; set; }
    public string AddressLine2 { get; set; }
}

我认为这个问题与以下事实有关 Agent拥有不止一处类型为 Address 的特性也可能是因为其中之一可以为空。我进行了一些搜索，但似乎找不到答案。

我想改变我的 Agent模型具有类型为 List<Address> 的单个属性那将使用 UserAddresses查找表会解决错误，但我更愿意保留当前模型而不是。

我该如何解决这个错误？提前致谢。

Answer 1

如果您的配置和您的型号不匹配，就会发生这种情况。

假设在您的数据库配置中您有这样的规则:

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    modelBuilder.Entity<Agent>().HasRequired(x=>x.MailingAddress);
    //..

但是在您的模型中您说 MailingAddress 是可选的:

public int? MailingAddressId { get; set; }

I believe the issue has something to do with the fact that Agent has more than one property of type Address and possibly also because one of them is nullable

事实并非如此。