c# - Entity Framework 无法在对象中插入重复键

Question

找不到我的问题的解决方案。对不起，如果我重复这个问题。

我在 Entity Framework 代码中首先有一对多的关系:

[DataContract(IsReference = true)]
public class PricingPlan
{

    public PricingPlan()
    {
        UserProfiles = new List<UserProfile>();
    }

    [Key]
    [DataMember]
    public Guid PricingPlanId { get; set; }

    [DataMember]
    public string Type { get; set; }

    public ICollection<UserProfile> UserProfiles { get; set; }
}

[DataContract(IsReference = true)]
public class UserProfile : IdentityUser
{
    public DateTime JoinedOn { get; set; }
    public DateTime LastVisited { get; set; }
    public string Location { get; set; }

    public Guid PricingPlanId { get; set; }
    public PricingPlan PricingPlan { get; set; }
}

在 PricingPlan 表中，我有 2 行 Free 和 Pro

当用户注册时，我想将他添加到免费计划中:

    [AllowAnonymous]
    [Route("Register")]
    public async Task<IHttpActionResult> Register(RegisterBindingModel model)
    {
        if (!ModelState.IsValid)
        {
            return BadRequest(ModelState);
        }

        PricingPlan pp = UnitOfwork.PricingPlanRepository.FirstOrDefault(v => v.Type == "Free");

        UserProfile user = new UserProfile
        {
            UserName = model.UserName,
            Email = model.Email,
            EmailConfirmed = false,
            Location = model.Location,
            JoinedOn = DateTime.Now,
            LastVisited = DateTime.Now,
            PricingPlanId = pp.PricingPlanId,
            PricingPlan = pp
        };

        IdentityResult identityResult = await UserManager.CreateAsync(user, model.Password);

我正在从 Db 获取现有计划并将其添加到 userProfile 属性，但是当 UserManager 尝试创建用户时，出现异常:

Violation of PRIMARY KEY constraint 'PK_dbo.PricingPlans'. Cannot insert duplicate key in object 'dbo.PricingPlans'. The duplicate key value is (a5139db8-64c1-49a2-97ef-55009259dc23).\r\nThe statement has been terminated."

OnModelCreating 我有这段代码:

  modelBuilder.Entity<UserProfile>().HasRequired<PricingPlan>(r=>r.PricingPlan).WithMany(c => c.UserProfiles).HasForeignKey(a=>a.PricingPlanId);

首先在 Entity Framework 代码中以一对多关系将现有实体添加到新实体的正确方法是什么？

Answer 1

好的，我解决了这个问题。

我删除了 PricingPlan = pp，如 markpsmith 所说。然后，当我想获取带有附加实体定价计划的 UserProfile 时， 我只是让包括:

this.Context.Set<UserProfile>().Include("PricingPlan").

但是无法理解，为什么默认不包含，当 LazyLoading 设置为 false 时。