c# - 实体框架代码优先方式——一对一关系

Question

我的模型协会（我相信）是一对一的：

public class Account
{
    [Key]
    [ForeignKey("BlockedAccount")]
    public virtual Guid AccountId { get; set; }
    public virtual string UserName { get; set; }

    public virtual BlockedAccount BlockedAccount { get; set; }
}

public class BlockedAccount
{
    [Key]
    public virtual Guid BlockedAccountId { get; set; }
    public virtual int BanLevel { get; set; }
    public virtual DateTime BannedDate { get; set; }
    public virtual DateTime ExpirationDate { get; set; }
    public virtual string Reason { get; set; }
}

但是当我尝试使用它时，程序崩溃了，它给了我以下异常：

INSERT 语句与 FOREIGN KEY 约束“FK_dbo.Accounts_dbo.BlockedAccounts_AccountId”冲突。冲突发生在数据库“Accounts”、表“dbo.BlockedAccounts”、列“BlockedAccountId”中。该语句已终止。

我在这里做错了什么？我想AccountId指出BlockedAccountId。

Answer 1

你是如何附加你的实体的？您不需要实际设置外键，只需附加到导航属性即可建立连接。这段代码，上面的模型对我有用：

     public class Account
{
    [Key]
    [ForeignKey("BlockedAccount")]
    public virtual Guid AccountId { get; set; }
    public virtual string UserName { get; set; }

    public virtual BlockedAccount BlockedAccount { get; set; }
}

public class BlockedAccount
{
    [Key]
    public virtual Guid BlockedAccountId { get; set; }
    public virtual int BanLevel { get; set; }
    public virtual DateTime BannedDate { get; set; }
    public virtual DateTime ExpirationDate { get; set; }
    public virtual string Reason { get; set; }

    public BlockedAccount()
    {
        BannedDate = DateTime.Now;
        ExpirationDate = DateTime.Now;
    }
}

public class Model : DbContext
{
    public DbSet<BlockedAccount> BlockedAccounts { get; set; }
    public DbSet<Account> Accounts { get; set; }
}
class Program
{

    static void Main(string[] args)
    {
        var b = new BlockedAccount()
            {
               BlockedAccountId = Guid.NewGuid()
            };
        var a = new Account();

        a.BlockedAccount = b;
        Model m = new Model();
        m.Accounts.Add(a);
        m.SaveChanges();
    }
}