Entity framework 实体框架：在运行Seed方法时，是否可以将新创建的记录的id插入到另一个记录中

尝试将一条记录上创建的id用于多条记录时出现问题

我的模型是这样的：

public class Student 
{
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int StudentId { get; set; }

    public int PersonId { get; set; }

    public string SID { get; set; }   

    public int AccountId { get; set; }

    public bool Active { get; set; }

    [ForeignKey("PersonId")]
    public virtual Person Person { get; set; }

    [ForeignKey("AccountId")]
    public virtual Account Account { get; set; }
}

public class Person
{
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int PersonId { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string MI { get; set; }
    public int SSN { get; set; }
    public int AddressId { get; set; }
    public int RaceId { get; set; }

    [ForeignKey("AddressId")]
    public Address Addresss { get; set; }  
}

 public class Address
{
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int AddressId { get; set; }
    public string StreetAddress { get; set; }
    public string City { get; set; }
    public string State { get; set; }
    public int ZipCode { get; set; }
}

使用以下命令为数据库设定种子：

context.Students.AddOrUpdate(x => x.SID,
    new WestCobb.Data.Student
    {
        SID = "99-B50-404324175",
        EnrollmentDate = Convert.ToDateTime("01-30-2017"),
        Active = true,
        Person = new WestCobb.Data.Person
        {
            FirstName = "Brian",
            LastName = "Folks",
            AddressId = 4,
            SSN = 404324175,
            Addresss = new WestCobb.Data.Address // This address!
            {
                StreetAddress = "5076 Lake Charles Court",
                City = "Chicago",
                State = "Illinois",
                ZipCode = 60208
            }
        },
        Account = new WestCobb.Data.Account
        {
            AccountNumber = "M00000000000088",
            AccountTypeId = 1,
            Priority = 1,
            Rate = 225.00m,
            BillingCycleId = 1,
            CreateDate = Convert.ToDateTime("01-30-2017"),
            Active = true
        }
    },
    // Manually set AddressId of this Person to AddressId of previous Person added 
    new WestCobb.Data.Student
    {
        SID = "99-A50-404527896",
        EnrollmentDate = Convert.ToDateTime("01-30-2017"),
        Active = true,
        Person = new WestCobb.Data.Person
        {
            FirstName = "Arthur",
            LastName = "Clue",
            SSN = 404527896,
            AddressId = context.Addresses.Last().AddressId // This seems not to work
        },
        Account = new WestCobb.Data.Account
        {
            AccountNumber = "W89322198433588",
            AccountTypeId = 1,
            Priority = 2,
            Rate = 225.00m,
            BillingCycleId = 1,
            CreateDate = Convert.ToDateTime("01-30-2017"),
            Active = true
        }
    }
);

并获取以下错误：

LINQ to Entities does not recognize the method 'WestCobb.Data.Address Last[Address](System.Linq.IQueryable`1[WestCobb.Data.Address])' method, and this method cannot be translated into a store expression.

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是否可以使用在第二个人地址中插入第一个人地址时创建的相同“id”（AddressId）？我想对多个人的地址Id使用相同的Id。

如果要对多个人使用相同的地址实体，为什么不先创建地址，然后根据需要多次使用它

var myAwesomeAddress = new WestCobb.Data.Address()
{
    StreetAddress = "5076 Lake Charles Court",
    City = "Chicago",
    State = "Illinois",
    ZipCode = 60208
};

// You should have a DbSet of your Addresses right ?
context.Addresses.AddOrUpdate(x => x.Id, // Use any discriminator
    myAwesomeAddress
);

context.Students.AddOrUpdate(x => x.SID,
    new WestCobb.Data.Student
    {
        SID = "99-B50-404324175",
        EnrollmentDate = Convert.ToDateTime("01-30-2017"),
        Active = true,
        Person = new WestCobb.Data.Person
        {
            FirstName = "Brian",
            LastName = "Folks",
            AddressId = 4,
            SSN = 404324175,
            Addresss = myAwesomeAddress
        }
    },
    new WestCobb.Data.Student
    {
        SID = "99-A50-404527896",
        EnrollmentDate = Convert.ToDateTime("01-30-2017"),
        Active = true,
        Person = new WestCobb.Data.Person
        {
            FirstName = "Arthur",
            LastName = "Clue",
            SSN = 404527896,
            Address = myAwesomeAddress // here
        }
    }
);

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太棒了！这实际上给了我比内联方法更大的灵活性。好建议，谢谢！！